Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Akabiz on 17/08/2019 04:38:17

Title: Was the Big Bang the beginning of the universe?
Post by: Akabiz on 17/08/2019 04:38:17
I am definitely not a physicist or astronomer by any means but I have a theory.  What if the Big Bang was not the beginning of the Universe but just an event in the universe?  The Big Bang could be an event that pushes dark matter outward like a large earthquake creates a tsunami in the ocean.  This could explain why the universe seems to be expanding faster in one direction then the other.  Also it could explain how HD 140283 looks like it’s older than the universe.  If this Big Bang event took place and the wave of dark matter overtook HD 140283 instead of destroying it, that would explain why it looks older then the universe.  Like the way a tsunami could overtake an island leaving it permanently covered by water.  The water is new but the island is older because it was there prior to the event.  So as the dark matter continues to extend outward from the event but it has left behind planets that were there prior to the Big Bang.  I know this is probably a stupid theory and has been thought of already and can immediately be disproven but thought I would throw it out there.  I love thinking about the universe and what is out there.  Thanks for your time and please don’t be too harsh.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: RobC on 17/08/2019 08:43:39
Sean Carroll believes the universe is infinite in both directions i.e. it never had a beginning, it was always there and it will never end.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bogie_smiles on 17/08/2019 12:58:38
I am definitely not a physicist or astronomer by any means but I have a theory.  What if the Big Bang was not the beginning of the Universe but just an event in the universe?  …
I love thinking about the universe and what is out there.  Thanks for your time …
As an elder member but with no administrative or operating connection to the Naked Scientists, welcome. I too love contemplating the nature of the universe and theorizing “what ifs” so I hope that you plan to engage in discussion at TNS.

In reply to the question positing no beginning, I would side with the thought that the Big Bang was not the beginning of the universe but was the initial event in our observable arena within the greater universe. I think of our observable universe as the space connected to our “local” big bang event which could certainly be one of an endless scenario of multiple similar events of “expansion, overlap, crunch and bang” here and there, now and then, across an infinite and eternal universe.

These collapse/bangs could be expected to expand, as ours appears to be doing, and eventually expansion could lead to arenas intersecting and overlapping with each other, causing the gravitational formation of galactic matter and energy into big crunches, which in turn reach a critical capacity and collapse/bang. Just speculating when I say that :) .
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Colin2B on 17/08/2019 14:43:58
I am definitely not a physicist or astronomer by any means but I have a theory.  What if the Big Bang was not the beginning of the Universe but just an event in the universe? 
It depends what you mean by ‘the universe’. Some, as @Bogie_smiles says take it to mean what we see today, others as @RobC indicates take it to mean a continuum in which a number of catastrophic events have occurred. Whichever way we take it, in our particular universe we don’t really know what happened before the period called inflation - although most cosmologists agree that there wasn’t a big bang from a singularity, to start everything off.
What happened before inflation is open to speculation, but no one is likely to be taken seriously unless they know a lot of physics and cosmology and can put together a very detailed hypothesis.

Certainly there are many who would say that there was not a period where nothing existed, probably as many would say it’s likely nothing existed before our universe.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: yor_on on 17/08/2019 15:26:46
I'll go with Sean and Collin :)
It was there, we can 'see' it looking back. But that doesn't tell us any more than that was when time started to 'tick', for us

13.7 (8) billions years ago, which may change :)
Time is a very strange idea.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CG on 25/08/2019 13:27:28
Who's to say we aren't looking at ourselves when looking at the universe? Maybe gravitational lensing is acting like a mirror and we are looking at our own selves.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 25/08/2019 14:45:17
Hi CG, welcome.

Quote
Who's to say we aren't looking at ourselves when looking at the universe?

Humphrey Bogart would have liked that.  “Here's looking at you, kid," :)

On a more serious note:

Quote
Maybe gravitational lensing is acting like a mirror and we are looking at our own selves.

This could let in CTCs and all the speculative flapdoodle that goes with them.  I don’t know enough about gravitational lensing to make an informed comment, but I struggle to think of a way in which it could give rise to a mirroring effect on a global level.  It will be interesting to see what the experts think.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 25/08/2019 15:00:21
Quote from: Colin
Certainly there are many who would say that there was not a period where nothing existed, probably as many would say it’s likely nothing existed before our universe.

Has anyone in the latter group actually explained how we could be here if there had ever been “nothing”? 

Fellow posters will know (only too well) that I subject TNS to recrudescences of the something from nothing debate, but I really am trying to keep an open mind. 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: yor_on on 25/08/2019 23:15:23
Maybe there exist a third possibility Bill, that we 'exist' as defined by the standard theory, universe included. But as you go down in scale we 'dissolve' into particles and forces. Gravity shrinks space according to relativity, and 'photons' acts and get acted upon by gravity. It seems to fall back on a question of 'energy'. With a infinite amount of energy, how would gravity behave?

Presume a infinite magnitude of energy, can there be created a toy model of a 'point'? We don't have one 'point' of conception though for this universe, as far as I see those 'points' exist everywhere. And we don't want to introduce a 'outside' because the logic for that will only lead us astray. It all hinges on dimensions being a construct though, not a origin. If that is correct then what you and me are becomes something more than just the sum of our parts.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 26/08/2019 18:36:43
Quote from: yor_on
Maybe there exist a third possibility Bill, that we 'exist' as defined by the standard theory, universe included.


That sounds a bit philosophical.  Who/what specified the “standard theory”?  How would that explain how something could come from nothing?

Quote
It seems to fall back on a question of 'energy'. With a infinite amount of energy, how would gravity behave?

Doesn’t that depend on how you define “infinite amount”?  Do you really mean “infinite” amount, or just an amount that is so large that we cannot measure it?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: yor_on on 28/08/2019 11:01:44
What I thought of referring to the standard theory is that is the best we have for the time being, but who and what defined it is a pretty long story. It's a model so maybe I should have named it that instead of calling it a theory. infinite should be infinite, there's a difference between assuming that a infinity is something countable although not possible for us to count and infinite as in uncountable. If you take religion I seem to remember a saying in where God can keep count of it all " how not one sparrow falls, that our heavenly Father, does not see it." and what it could be seen to represent is the first proposition in where a 'infinity' becomes something 'countable', although not for us.  But that's not my view of it. If you think of a infinite universe then the idea must be that no matter where you are you still will find a 'bubble of light' around you 13.8~billion light years, no matter how far you go. That I think is a good example of a real infinity.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: yor_on on 28/08/2019 11:08:20
You can also think of a infinity as something represented by 'photons' which represent a limit of propagation 'c'. If we assume that you could take a particle of mass and wind it up to being infinitely close to 'c'. Would you expect it to meet a wall somewhere? The universe must 'shrink' for it but will it 'stop' its propagation?
=

you will need some presumptions for that one, as ignoring gravity and being in a 'perfect vacuum', but the idea still works.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 28/08/2019 13:35:21
The reason I queried the “standard theory” was that you seemed to be presenting it as a possible answer to my question: “Has anyone in the latter group actually explained how we could be here if there was ever “nothing”?”.

For me, the something-from-nothing question is closely linked to thoughts about infinity and eternity.   

Occasionally, I quote Krauss as saying: “By nothing, I do not mean nothing…..” I admit that this is only part of what he said, so is probably not a fair quote.  I defend it on the grounds that, for me, it sums up the something from nothing argument as it is customarily presented; and it’s “fun”.

One may, perhaps, need to take a closer look at his book to register his admission, towards the end, that every-thing he has been talking about simply takes the basic principles of quantum mechanics for granted.

It seems that it all hinges on the laws of quantum mechanics.

Where are these laws supposed to have come from? Surely quantum mechanics must be something, or be relate to something; and that something must have predated the “writing” of the laws.  Krauss - a little grudgingly – confesses to not having a clue on this particular issue.  Somehow, he seems to think it doesn’t matter.  Possibly, it doesn’t matter, but I have a feeling that the question as to how – not why – we are here is something that scientists should not relegate to semantic triviality.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 28/08/2019 13:53:49
A long history underlies the search for, and interpretation of, the fundamental laws of nature; but these laws take it for granted that there is, essentially, a persisting, physical “something”.

The fundamental physical laws that Krauss talks about are the laws of relativistic quantum field theories.  Presumably, these quantum fields constitute the most up-to-date version of the underlying “something”.  The scientific “world view” has become more arcane, but the basic position has not changed.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: yor_on on 29/08/2019 19:34:39
That's a difficult proposition Bill, that it doesn't matter. I would say it do matter, at least for me. There are some things I try to avoid, like creating self fulfilling ideas. Like circles inside circles inside circles of logic. They don't lead anywhere. But it's also a question of how you define it. Can one just find a way to define it in where it makes sense it will be interesting. As for example the way I want to define dimensions as something 'created' instead of a origin. To me it makes sense :)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: yor_on on 29/08/2019 19:36:23
For your other post I would refer to statistics, and the way we try to interpret those.
Title: Was the Big Bang the beginning of the universe
Post by: AustinnEp on 06/09/2019 11:47:19
The first sentence from the SpaceDaily article reporting this caught my attention:Although for five decades, the Big Bang theory has been the best known and most accepted explanation for the beginning and evolution of the Universe, it is hardly a consensus among scientists.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 06/09/2019 18:48:59
A quick skim through the article left me thinking: It's an interesting article, but what's new, here? Could the most significant word be "reintroduces" ?  He seems to hold an outmoded view of the "Big Bang Singularity", and describing the Big Bang as an explosion is a bit misleading.

I'll try to find a few minutes to read it properly; I might need to apologise to the author. :)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: jeffreyH on 06/09/2019 20:06:25
Sean Carroll believes the universe is infinite in both directions i.e. it never had a beginning, it was always there and it will never end.

Entropy? Heat death? You would need a way of perpetually undoing the increase in entropy AND be consistent with the laws of thermodynamics.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: esquire on 06/09/2019 23:01:21
As  for common science dogma, everything in the Universe is a wave. That implies momentum and locality cannot be mutually established under the uncertainity principle. The Big Bang Theory, says it occurred 14.5 billion years ago, this is a measurement of velocity in light years and an assumption of locality. 14.5 billion light years ago to present, is a velocity approximation. 14.5 billion years ago is also  a locality assumption.

Is the Universe's initial rapid expansion an exception to the uncertainity principle? Backwards engineering the Universe's age for locality and expansion velocity,  says it is.

The Higgs Boson creates a wave energy signature at the location of the particles collision. Its gaussian wave signature is recorded and it energy disappears from sensor detection. The magnetic resonance detectors which are capable of recording objects at the speed of light, observe the Higgs Boson at the initial location with its speed of light velocity. So, initially, it's wave location, and it wave velocity are determined. But then it's energy disappears completely, with no sign of decay or annilation of its energy which is a violation of the law of conservation. This presents an issue, how and where did this energy disappear to?  Such are the mystery's of science!



Title: Re: Was the Big Bang the beginning of the universe?
Post by: esquire on 07/09/2019 01:18:19


Is the Universe's initial rapid expansion an exception to the uncertainity principle? Backwards engineering the Universe's age for locality and expansion velocity,  says it is.



Was the initial expansion  of the Universe, faster then the speed of light?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: esquire on 07/09/2019 01:38:47


Is the Universe's initial rapid expansion an exception to the uncertainity principle? Backwards engineering the Universe's age for locality and expansion velocity,  says it is.



Was the initial expansion  of the Universe, faster then the speed of light?

Was the Big Bang essentially the creation of a new dimension?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: esquire on 07/09/2019 04:03:27
Can  momentum/velocity be a defining parameter for dimensionality?  Would exceeding the speed of light place one in a different separate dimension?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: flummoxed on 07/09/2019 10:29:22
It seems that it all hinges on the laws of quantum mechanics.Where are these laws supposed to have come from? Surely quantum mechanics must be something, or be relate to something; and that something must have predated the “writing” of the laws.  Krauss - a little grudgingly – confesses to not having a clue on this particular issue.  Somehow, he seems to think it doesn’t matter.  Possibly, it doesn’t matter, but I have a feeling that the question as to how – not why – we are here is something that scientists should not relegate to semantic triviality.

This is a bit speculative, but to answer your question; something I have stumbled across recently is SED Stochaistic Electro Dynamics. It attempts to explain the Physics behind Quantum Mechanics, based on the zero point energy of the vacuum. It is a deterministic theory being developed by a number of researchers around the world.

Title: Re: Was the Big Bang the beginning of the universe?
Post by: flummoxed on 07/09/2019 10:33:55

Was the initial expansion  of the Universe, faster then the speed of light?

According to the various inflationary models around yes it was. The inflationary stage of the existing visible universe, speculating might have been the cause of the baryogenesis and hot big bang. The growth of our visible universe is expanding at an accelerating rate. At some stage in the future it could reach inflationary growth rates and again, and who knows another big bang.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 07/09/2019 17:31:21
https://www.quantamagazine.org/big-bounce-models-reignite-big-bang-debate-20180131/

I think this is worth a look.  Some of its ideas seem a bit “way-out”, but there’s a lot to think about.

Quote
“Imagine there’s just one of these curled-up extra dimensions, a tiny circle found at every point in space. As Graham put it, “At each point in space there’s an extra direction you can go in, a fourth spatial direction, but you can only go a tiny little distance and then you come back to where you started.”

Am I alone in seeing a major snag here?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 07/09/2019 17:47:11
Was the Big Bang the beginning of the universe?

If what you call "the universe" is everything which is real, then no. The idea that the Big Bang comes from nothing comes from the mixing of three main ideas, each is unproven.

1- There is a vacuum field which has an independent existence of the matter field.
2- Randomness is fundamental.
3- There is a multiverse. (this one is a kind of a consequence of the other 2)

The nothing is not nothing but the vacuum field. Some physicists think that the total energy of the vacuum field is zero. There is an equal amount of positive and negative energy (attraction vs repulsion). But nevertheless, you need constant fluctuations of the field to create matter. The randomness sweeps this necessity under the rug.

The problem is that gravity is not unified with Quantum Mechanics, so this is speculations. From Einstein's point of view, there shouldn't be any vacuum fields in absence of matter. Furthermore, the universe could have no beginning and no end but be finite in energy and space. In fact, this makes more sense if you consider the quantization of the elements which implies some sort of limits on the fields. How such limits could exist in an infinitely large universe? It leads to infinite regressions upon infinite regressions leading to no limit at all...
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 07/09/2019 19:48:13
 
Quote
How such limits could exist in an infinitely large universe? It leads to infinite regressions upon infinite regressions leading to no limit at all...

The ultimate apagoge!
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 07/09/2019 20:00:11
Quote
Some physicists think that the total energy of the vacuum field is zero. There is an equal amount of positive and negative energy

Isn't this conclusion based on the apparent belief that zero net energy and zero total energy are synonymous?
Wouldn't that belief be erroneous?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 07/09/2019 20:25:59
"How such limits could exist in an infinitely large universe? It leads to infinite regressions upon infinite regressions leading to no limit at all..."

It is not a proof but I invoke Occam's razor. You may add fixed parameters resulting in more fine tuning. Same for your other question. Hi Bill!
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 07/09/2019 20:33:32
To your second question, yes. My point of view is there is no negative energy, there is just inflows and outflows of mass-energy. There is attraction and repulsion but no negative energy. I must stop here because it is just a theory... A last comment: Time and space have asymmetries which generate the structure of matter and space-time. That's how you get only positive energy. Time is the dynamics. Think about the Equivalence Principle.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 08/09/2019 02:37:15
Quote from: Jeffrey
Entropy? Heat death? You would need a way of perpetually undoing the increase in entropy AND be consistent with the laws of thermodynamics.

Just a thought about the entropy involved.  although scientists assure us that they can follow the course of the expansion of the Universe backwards to an unimaginably small fraction of a second after the Big Bang, they cannot actually reach it.  It follows, therefore, that at the point at which the “known” history of the Universe starts, the Universe already existed.

Thus, the BB doesn’t explain the “presence” of the Universe.  However, it does seem to indicate that entropy was very low at the start.  Is this the case?

If no “new” matter/energy has been “created” since the BB; it follows that, initially, the entire Universe was compacted into an unimaginably small “space”.   

At the start, the entropy of the Universe must have been at its maximum.  There were few, if any, ways in which the contents could be distributed.  Only when the Universe began to expand would there have been room for possible variations of the state of the quark/gluon plasma, or whatever the composition was.

The “creation” of space lowered the entropy by providing the potential for “work”. 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: flummoxed on 08/09/2019 11:21:46
If no “new” matter/energy has been “created” since the BB; it follows that, initially, the entire Universe was compacted into an unimaginably small “space”.   

No it does not, the Big bang is a model of the visible universe. Space is expanding, and a microscopic volume of space now in a few trillion trillion years will occupy a larger volume of space.

Thus, the BB doesn’t explain the “presence” of the Universe.  However, it does seem to indicate that entropy was very low at the start.  Is this the case?

Entropy of space is tending towards zero as the universe expands. See Penroses ideas. The big bang might repeat itself over and over again in different Aeons.

It follows, therefore, that at the point at which the “known” history of the Universe starts, the Universe already existed.

Why should a universe not already exist.

------------

The HUP does not violate the laws of thermo dynamics because it only borrows energy from the vacuum of space momentarily. The Zero point energy of the vacuum, is theoretically zero. The Casimir effect proves it exists.. It is not beyond the realms of possibility that the inflation of a region of space separated virtual particle pairs from the vacuum of space causing baryogenesis. Not unlike Hawking radiation around Blackholes.

A pop science link to SED, this link got me interested. http://www.calphysics.org/zpe.html It seems that the zero point vacuum energy of space might be behind the HUP the expansion of space how atoms are created, entanglement etc etc. SED has been under development for about 30 years by various theoretical physicists.

Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 08/09/2019 13:41:12
Quote
  No it does not, the Big bang is a model of the visible universe. Space is expanding, and a microscopic volume of space now in a few trillion trillion years will occupy a larger volume of space.

Are you saying that about 10-43s after the BB, the “visible universe” did not occupy “an unimaginably small space”?  If you are not; I struggle to see the relevance of the comment, however correct it might be in itself.

Quote
Entropy of space is tending towards zero as the universe expands.

I do my best with entropy. :)  I thought it was increasing as the Universe expands, but I could have that wrong.

Quote
See Penroses ideas. The big bang might repeat itself over and over again in different Aeons.

No argument there, but I don’t see the relevance to the entropy of the nascent Universe.

Quote from: Bill
It follows, therefore, that at the point at which the “known” history of the Universe starts, the Universe already existed.

Quote from: Flummoxed
Why should a universe not already exist.

If my quote suggested that the Universe should not already have existed, it was unintentional.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: flummoxed on 08/09/2019 15:37:17
I do my best with entropy.   I thought it was increasing as the Universe expands, but I could have that wrong

Yes the overall entropy of the universe is increasing. However in space there isnt much there except galaxies. As the universe continues to expand and all the visible galaxies and bits of rock dissappear over your visible horizon you are effectively in an area of space with a very low entropy ie it tends towards zero, because there aint nothing there :( except zero point energy of the vacuum, which might be what drives the expansion of space.


Are you saying that about 10-43s after the BB, the “visible universe” did not occupy “an unimaginably small space”?  If you are not; I struggle to see the relevance of the comment, however correct it might be in itself.

OK I suspect you are taking the piss :) But lets say in a volume of space the size of a grapefruit devoid of matter and therefore zero entropy, it starts to expand at speeds not seen before the inflationary stage of the big bang model due to the zero point energy of the vacuum. This expansion is so fast that virtual particles are separated and become real causing baryogenesis and Big Bang nucleo synthesis the universe as we know it etc Until the next Aeon
 
No argument there, but I don’t see the relevance to the entropy of the nascent Universe.

https://en.wikipedia.org/wiki/Conformal_cyclic_cosmology

Title: Re: Was the Big Bang the beginning of the universe?
Post by: flummoxed on 08/09/2019 15:49:30
At the start, the entropy of the Universe must have been at its maximum.  There were few, if any, ways in which the contents could be distributed.  Only when the Universe began to expand would there have been room for possible variations of the state of the quark/gluon plasma, or whatever the composition was.

The “creation” of space lowered the entropy by providing the potential for “work”. 

You are agreeing with me here I think. Expansion of space reduces the entropy locally in that region of space.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 08/09/2019 18:28:52
We are, probably trying to cover too many points at once, so I’ll start with just one point from your last post.  Hopefully we can clear that up before moving to the next.

Quote
Yes the overall entropy of the universe is increasing. However in space there isnt much there except galaxies. As the universe continues to expand and all the visible galaxies and bits of rock dissappear over your visible horizon you are effectively in an area of space with a very low entropy…….

If we are considering the entropy of the Universe a fraction of a second after the BB; we are certainly looking at the whole Universe.  It becomes important to distinguish clearly between the Universe (= observable universe) and anything else that might be hypothesised to exist.

E.g. in
 
Quote
] No it does not, the Big bang is a model of the visible universe. Space is expanding, and a microscopic volume of space now in a few trillion trillion years will occupy a larger volume of space.
You seem to be saying that I cannot make a specific proposal about the entropy of the Universe just after the BB, because some unspecified “volume of space” will expand in the distant future.   Is that right?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: flummoxed on 09/09/2019 10:30:12
You seem to be saying that I cannot make a specific proposal about the entropy of the Universe just after the BB, because some unspecified “volume of space” will expand in the distant future.   Is that right?

There is a lot to this question. You appear to be assuming a closed area of space, which might not have been the case.
Rather than me waffle on here is a link from Ethan https://www.forbes.com/sites/startswithabang/2017/04/15/ask-ethan-what-was-the-entropy-of-the-universe-at-the-big-bang/#7b2b4ac27280

The laws of thermodynamics in the Big bang seem a bit muddled dont you think? My point being the big bang theory is only a mathematical model, which you will note does not require the high degrees of proof required in other sciences, particle physics for example. So when I look at it, I dont believe it is proven fact. It is only the current favored evolving model of the universe. Other interesting models exist, and perhaps some where in the middle of them all lies the truth.

Cosmic Cyclic Cosmology, Quantum Loop Gravity, etc etc >  the list goes on. Some of which might be partly plausible and others appear to be science fiction.

The CMBR appears to support a hot dense state of photons that spread out filling all of space. But would there be any difference to the model, if at the end of the inflationary epoch baryogenesis occurred, without the original hot dense state?
I think in my simple way of looking at things, this fits the data without all matter in the universe coming out of an area the size of a grapefruit.

It is possible if Hawking radiation is correct, that the inflation of space might have caused particle production, from the zero point energy of the vacuum.  Here is a wiki on the subject https://en.wikipedia.org/wiki/Zero-point_energy

Edit just remembered this link posted some time ago https://profmattstrassler.com/2014/03/17/my-new-articles-on-big-bang-inflation-etc/ enjoy
Title: Re: Was the Big Bang the beginning of the universe?
Post by: flummoxed on 09/09/2019 14:52:00
Edit to answer the OP was the big bang the beginning of the universe? Likely it was not the beginning of the entire universe, maybe just the visible universe.

Ref various different views on inflationary models http://universe-review.ca/R02-13-inflation.htm this is a quick overview.

I like the idea of repeated big bangs, in an already existing universe. It appears to step around the need for inflation and a beginning of time. Our visible universe might be circa 40 billion years old, but an older universe likely exists beyond what can be observed.

Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 09/09/2019 17:20:23
Flummoxed, I'm unlikely to have time to follow the links in #37 for a while.  I've found both Siegel and Strassler very helpful in the past.  In the meantime:

Quote
I like the idea of repeated big bangs, in an already existing universe. It appears to step around the need for inflation and a beginning of time. Our visible universe might be circa 40 billion years old, but an older universe likely exists beyond what can be observed.

Starting everything at the BB, or any specific point, involves the something-from-nothing problem.
Multiple, bouncing or otherwise repeating universes, run into "Turtles-all-the-way-down" problem.
What about an infinite, eternal, changeless cosmos, of which our Universe is a 3+1D "shadow". No creation from nothing, no infinite regression!   

Just a thought.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Colin2B on 09/09/2019 18:30:38
Starting everything at the BB, or any specific point, involves the something-from-nothing problem.
I think that’s why flummoxed was specific in saying ‘visible universe’; you could also call it the current universe, so no  something from nothing needed.
You need to be clear about what you mean by ‘the universe’.

Multiple, bouncing or otherwise repeating universes, run into "Turtles-all-the-way-down" problem.
What about an infinite, eternal, changeless cosmos, of which our Universe is a 3+1D "shadow". No creation from nothing, no infinite regression!   
To be honest it still doesn’t answer the question whether our something could emerge from nothing, or even what we might mean by that nothing.
We've had lots of debates on this and they generally go nowhere because none of us have a deep enough knowledge of the physics involved to make a reasonable contribution. Infinite debate  ;D
Title: Re: Was the Big Bang the beginning of the universe?
Post by: flummoxed on 09/09/2019 19:11:34
Starting everything at the BB, or any specific point, involves the something-from-nothing problem.
Multiple, bouncing or otherwise repeating universes, run into "Turtles-all-the-way-down" problem.
What about an infinite, eternal, changeless cosmos, of which our Universe is a 3+1D "shadow". No creation from nothing, no infinite regression! 

No one was around in the big bang, to see it happen, it is not beyond the realms of possibility that it did not happen as described in the various models. You raise an extra dimension, is that like a collapsed dimension in a black hole, an unfolded dimension in string theory or a membrane connecting all points in space. We could live inside a BH with an extra dimension Podolsky russian guy.

Can you expand on what you mean.

Zero point energy of the vacuum, and gets around the laws of thermodynamics by only borrowing momentarily the energy then giving straight back.  BUT
Title: Re: Was the Big Bang the beginning of the universe?
Post by: flummoxed on 09/09/2019 19:14:20
We've had lots of debates on this and they generally go nowhere because none of us have a deep enough knowledge of the physics involved to make a reasonable contribution. Infinite debate

I learn a lot by speculating. I find in many instances some one theoretically clever has already had the idea.:) 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 10/09/2019 12:48:18
Quote from: Colin
You need to be clear about what you mean by ‘the universe’.
Using the “Universe, universe, cosmos” distinction is an attempt at clarity.  Here, I said “everything”, as I thought that might avoid confusion arising from interpretations of “universe”.  What could there be that is not included in “everything”?

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To be honest it still doesn’t answer the question whether our something could emerge from nothing…

Of course it doesn’t, but it does remove the need to ask the question in the first place.

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…, or even what we might mean by that nothing……. none of us have a deep enough knowledge of the physics involved to make a reasonable contribution. 

Surely, if physics is involved, we are already talking about “something”.  How would you define “the physics of nothing” without treating “nothing” as “something”? 
This is not just a facetious question.  Discussing “nothingness” or “infinity” does tend to cause heads to be firmly inserted up semantic arses, which is unfortunate.  As you rightly say: "Infinite debate".
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 10/09/2019 18:00:45
Quote from: Flummoxed
No one was around in the big bang, to see it happen, it is not beyond the realms of possibility that it did not happen as described in the various models.

That’s why they are models, not dogmatic statements.

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You raise an extra dimension, is that like a collapsed dimension in a black hole, an unfolded dimension in string theory or a membrane connecting all points in space.

Nothing so complex; just 3 of space + time.

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Can you expand on what you mean.

If you mean “The Infinite Cosmos”,  I’ll have to come back to you on that.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: flummoxed on 10/09/2019 22:36:18
Discussing “nothingness” or “infinity” does tend to cause heads to be firm

This is an interesting philosophical statement, infinite (unfolded space time dimensions) + nothing (none space time dimensions ) could exist at the same time. Space does appear to be expanding between galaxies, and perhaps contracting near mass in some way causing the curvature of space time.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 11/09/2019 13:05:49
Quote from: Flummoxed
Can you expand on what you mean.

Can we try an experiment?

I Posted the following some months ago, and got no response.  I’d like to try it from a different perspective.  Patience, please.  The idea is to look at the logic, or otherwise, of the whole line of reasoning.

Start be assuming that statements 1 – 4 are correct.  Their veracity can be demolished later!

For the moment, forget about mathematics, we can come to that later.

1. Something must always have existed.  Let’s call that “something” the cosmos.
2. The cosmos (everything that is, or ever can be) is infinite, unchanging and indivisible.
3. If the cosmos is indivisible; everything that we might consider as a part of the cosmos, is the cosmos.
4. The Universe (that which we perceive as starting at the BB) is “embedded” in the cosmos.

By the above reasoning, we must say that the Universe “is the cosmos”.
The only way in which this reasoning could be logically consistent would be if the Universe were a “shadow” of the cosmos.  (Think of the analogy of the people in a cave who could see only shadows on the wall).
Time, change and progression are features of this “shadow” reality.  They have meaning only in our perceived Universe.
It might be argued, from this, that our Universe is an illusion, but this has no real significance, because this illusion, is our reality.  It is all we are able to observe and study.  This, of course, is where we would re-introduce maths; and start questioning the initial statements.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: flummoxed on 11/09/2019 15:30:29
By the above reasoning, we must say that the Universe “is the cosmos”.
The only way in which this reasoning could be logically consistent would be if the Universe were a “shadow” of the cosmos.  (Think of the analogy of the people in a cave who could see only shadows on the wall).
Time, change and progression are features of this “shadow” reality.  They have meaning only in our perceived Universe.

I accept your definition that the entire physical universe is this cosmos, it follows that the observable universe is a part of the cosmos. How does this reasoning lead to an illusion.

The analogy to shadows on wall implies 3 or more dimensions, being projected onto a 2D surface. Dimensions dont have to be spacial, take maybe time for instance, or maybe membranes or worm holes through space time. How would they appear reflected on a wall??

Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 11/09/2019 20:30:45
Quote
Start be assuming that statements 1 – 4 are correct.  Their veracity can be demolished later!

I'm not suggesting that anyone should actually accept these statements, other than as a test of the logic, IF they were correct.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 12/09/2019 00:27:33
Start be assuming that statements 1 – 4 are correct.  Their veracity can be demolished later!

For the moment, forget about mathematics, we can come to that later.

1. Something must always have existed.  Let’s call that “something” the cosmos.
2. The cosmos (everything that is, or ever can be) is infinite, unchanging and indivisible.
3. If the cosmos is indivisible; everything that we might consider as a part of the cosmos, is the cosmos.
4. The Universe (that which we perceive as starting at the BB) is “embedded” in the cosmos.
I will ignore the fact that I have issues with the statements.
1 and 2 seem mutually contradictory.  1 defines cosmos not as 'all there is', but as something that has always existed, implying my mailbox is not part of the cosmos because it was created only 8 years ago.  I think #1 just needs to be worded more carefully.

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By the above reasoning, we must say that the Universe “is the cosmos”.
The only way in which this reasoning could be logically consistent would be if the Universe were a “shadow” of the cosmos.  (Think of the analogy of the people in a cave who could see only shadows on the wall).
Time, change and progression are features of this “shadow” reality.  They have meaning only in our perceived Universe.
If time is a feature of this shadow reality, then time is not fundamental to the cosmos, in which case point 1 cannot have a reference to time.  By the usage of past tense, you imply a statement that there is not a time in which this thing did not exist, but if time is only part of the shadow reality started at the BB, then it is meaningless to reference times of the existence of the cosmos.  It's like drawing a graph on a computer screen and then asking for the x/y coordinates of the computer on that graph.

BTW, I've never seen 'cosmos' used as a synonym for a container for the universe.  I'm more likely to see universe as the container, and say 'inflation bubble' as all that 'started' and continues from the big bang.  Inflation bubble is still arbitrarily larger than 'visible universe'.  I'm fine with the nonstandard terminology, but find it unintuitive.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: RobC on 12/09/2019 09:12:31
I recollect the words of John Wheeler, he concluded:

Can we ever expect to understand existence?
Clues we have and work to do, to make headway on that issue.

Surely someday, we will grasp the central idea of it all as so simple, so beautiful, so compelling that we will all say to each other, “Oh, how could it have been otherwise! How could we all have been so blind so long”!

Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 13/09/2019 14:05:33
Quote from: Flummoxed
I accept your definition that the entire physical universe is this cosmos, it follows that the observable universe is a part of the cosmos. How does this reasoning lead to an illusion.

Try “accepting”:  2. “The cosmos (everything that is, or ever can be) is infinite, unchanging and indivisible.”
Think about the unchanging and indivisible aspect of the cosmos, and compare that with the obviously changing and divisible nature of the Universe.  Then ask how one could be “part” of the other.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Colin2B on 13/09/2019 15:13:10
Try “accepting”:  2. “The cosmos (everything that is, or ever can be) is infinite, unchanging and indivisible.”
Think about the unchanging and indivisible aspect of the cosmos, and compare that with the obviously changing and divisible nature of the Universe.  Then ask how one could be “part” of the other.
So you’re saying that people, plants, planets etc can’t be part of the ‘cosmos’ because they change?

Why do you think the ‘cosmos’ you’ve defined is unchanging? Experience says otherwise.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 13/09/2019 16:06:02
Quote from: HalC
I will ignore the fact that I have issues with the statements.

Thanks for doing that.  I have issues with the statements, as well.  Over a considerable number of years, I’ve reached a degree of satisfaction with a lot of these, but there are still a few to go. That’s what I’m trying to work on now.

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.  I think #1 just needs to be worded more carefully

I would be very happy to consider rewording (I’ve done it several times, already) as long as the meaning remains, essentially, the same.  Is it “Something must always have existed” that causes problems? 
The concept it is meant to convey is:  There can never have been “nothing”, therefore, there must always have been “something”.  Do you have issues with that?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 13/09/2019 16:43:40
Quote from: Colin
Why do you think the ‘cosmos’ you’ve defined is unchanging? Experience says otherwise.

I think (hope) we may be working towards that, but, if not, don't let me overlook it.  It's an important point, but can lead down a lot of "blind alleys". 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 13/09/2019 16:57:22
Quote from: RobC
Surely someday, we will grasp the central idea of it all as so simple, so beautiful, so compelling that we will all say to each other, “Oh, how could it have been otherwise! How could we all have been so blind so long”!


Good thought, but I think I can confidently predict that I’ll not be around to see it. :)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 13/09/2019 20:27:16
Quote
.  I think #1 just needs to be worded more carefully
I would be very happy to consider rewording (I’ve done it several times, already) as long as the meaning remains, essentially, the same.  Is it “Something must always have existed” that causes problems?
That wording makes it sound like the cosmos is just one of a collection of things, one that has always existed, unlike some of the others.
This contrasted with number 2 that defined cosmos differently, as 'all that is', precluding these other things.

The change of verb tense is also inconsistent between the two.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 14/09/2019 12:26:36
Quote from: HalC
By the usage of past tense, you imply a statement that there is not a time in which this thing did not exist, but if time is only part of the shadow reality started at the BB, then it is meaningless to reference times of the existence of the cosmos.


Nice one, HalC!  You’ve hit the two problems that so often lead to circular arguments that never go anywhere.

Problem 1:  The only language we have in which to talk about infinity, is our finite-based language. 

Problem 2:  If the cosmos is changeless and indivisible; how can the changing Universe be part of it?  More fundamentally, how can anything be part of it, if it is indivisible?

Does problem 2 equate, in any way, to the reasoning in your quote, above?

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1 and 2 seem mutually contradictory.  1 defines cosmos not as 'all there is', but as something that has always existed, implying my mailbox is not part of the cosmos because it was created only 8 years ago.

I think this is a matter of interpretation. 1 asserts that there must always have been something.  2 qualifies this by saying something about this “eternal something”.  Neither implies that your mailbox is not part of the cosmos.

Of course, using any tense, other than the “present indicative”, when referring to eternity is inappropriate, but just saying “Something is”, might well be interpreted as being different from saying “Something has always existed”.  Any suggestions for de-confusing it?

I’m not a great fan of John Gribbin, but I find that his terminology, in this case, can be useful, reduce verbosity.

Cosmos = everything that exists, or can exist.
Universe = our (in principle) observable portion of spacetime and its contents.
universe = any other universe that may, or may not, exist.

See https://www.thenakedscientists.com/forum/index.php?topic=73511.msg548859#msg548859 #107.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 14/09/2019 16:38:01
Quote from: HalC
By the usage of past tense, you imply a statement that there is not a time in which this thing did not exist, but if time is only part of the shadow reality started at the BB, then it is meaningless to reference times of the existence of the cosmos.

Nice one, HalC!  You’ve hit the two problems that so often lead to circular arguments that never go anywhere.

Problem 1:  The only language we have in which to talk about infinity, is our finite-based language.
The mixing of tenses is unrelated to discussions about infinity.  There is a language for it, but it needs to be used correctly.  So saying that the 'cosmos is infinite' is a vague statement that there is some property of said cosmos that is not bounded, but without identification of the property in question.

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Problem 2:  If the cosmos is changeless and indivisible; how can the changing Universe be part of it?  More fundamentally, how can anything be part of it, if it is indivisible?
Yes, your prior posts identified this problem.
 The statement asserts both that the cosmos exists in time and that it is in identical state at any pair of different times.  I find both assertions hard to defend, but you said not to worry about the veracity of the statements, so I didn't comment on it.  That problem is easily solved by putting time in the structure and not the structure in time.  The latter violates the cosmos being all there is: The cosmos and time are two things.  Three if you posit space that it occupies.

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Does problem 2 equate, in any way, to the reasoning in your quote, above?
I think so yes.  Your problem 2 used wording implying time as a container for 'comsos', and my problem that you quote above talks about exactly that as well.  If cosmos is all there is, it cannot be in a container. Can't have it both ways, or you'll just keep running into these contradictions.

Mind you, I think I've found a solution to all these problems, but it's kind of a long journey where you need to choose compatible interpretations of time, mind, QM, and identity.  Don't need to understand them all, but you need to be aware of their respective implications.

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1 and 2 seem mutually contradictory.  1 defines cosmos not as 'all there is', but as something that has always existed, implying my mailbox is not part of the cosmos because it was created only 8 years ago.
I think this is a matter of interpretation. 1 asserts that there must always have been something.  2 qualifies this by saying something about this “eternal something”.  Neither implies that your mailbox is not part of the cosmos.
By 'eternal', do you mean 'for all of time' (the cosmos being contained in unbounded time), or do you mean eternalism/block-universe/time being part of (contained by) the cosmos or parts of it?
If the former, you're on your own, because it demotes cosmos to an object within a larger thing.
If the latter, you cannot meaningfully use tensed verbs when discussing things, which is why I jumped all over the switching of verb tense.

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Of course, using any tense, other than the “present indicative”, when referring to eternity is inappropriate, but just saying “Something is”, might well be interpreted as being different from saying “Something has always existed”.  Any suggestions for de-confusing it?
I say 'something is'.  Giving a reference to a preferred moment in time that doesn't exist under the view always leads to confusion.  There is no 'the past' in the view, so the dinosaurs exist as much as anything.  They're not in a state of 'existed', except in a relation to a specifically identified time in their future.

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Cosmos = everything that exists, or can exist.
Universe = our (in principle) observable portion of spacetime and its contents.
universe = any other universe that may, or may not, exist.
As for Universe, the line isn't very abrupt.  It sort of fades away.  Sure, we have theoretical information on stuff 45 BLY away (depending how you measure it), but that doesn't mean planet X exists just because it's within that radius. Not if we cannot have knowledge of it. This gets into the sort of issues that come up with QM interpretations.  Some of them very much do say that X exists, despite our lack of knowledge of it.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 14/09/2019 18:00:30
Thanks for that interesting post. There’s a lot in it I would like to return to, but time’s short. 

I must comment on one point, though.

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By 'eternal', do you mean 'for all of time' (the cosmos being contained in unbounded time),

No! Eternity is not time.  The cosmos is not contained in anything.  In what way does "eternal" imply containment in anything?

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If the former, you're on your own, because it demotes cosmos to an object within a larger thing.

I would be interested to see the process by which you reach that conclusion.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 14/09/2019 19:56:44
Quote
By 'eternal', do you mean 'for all of time' (the cosmos being contained in unbounded time),
No! Eternity is not time.  The cosmos is not contained in anything.
Good.  Just checking.

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If the former, you're on your own, because it demotes cosmos to an object within a larger thing.
I would be interested to see the process by which you reach that conclusion.
Everyone uses language for objects (the only things we know) to describe things which are not in the category of objects.  Objects are 'created' and usually have a finite span of time and space in which they exist.  So to pick one (me), there are points in time which are not simultaneous with any event at which I am present.  Thus I am not not eternal (by the first definition, which you're not using).  I can use tensed language with reference to myself: Before me, during me, after me. 'I have always existed' is false regardless of the selected 'present' moment with which such syntax relates.
Objects are members of a set, but the set is not a member of the set. Objects are thus 'contained' by the set.  They're existing members of it. Thus it makes no sense to use such syntax to non-objects like 'cosmos'.  To use such language implies its membership in a larger set, one with the cosmos as a member, even if the only member.

Hence I have a real problem with statements like 'the cosmos exists' because that language implies membership of 'cosmos' in a larger set of things that exist.  This paradox vanishes if 'exists' is a relation (between object and set) instead of a property.  My mailbox thus doesn't have the property of existence.  What is has is the relation of existence with the cosmos.  The cosmos contains my mailbox.  Almost everything is a relation to me.  It seems free of contradictions, even if it isn't entirely intuitive.  I had to discard what turned out to be several basic biases I held, some of which I still believe despite knowing them to be false. Proof that the rational side of me is not in charge I guess.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 14/09/2019 20:48:24
Are you a physicist?  :)

https://www.thenakedscientists.com/forum/index.php?topic=65009.msg475694#msg475694      #5
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 15/09/2019 01:36:24
Are you a physicist?  :)
Well, my answer is not absolutely right, since it's philosophy, not physics, being discussed. You've been asking philosophical questions in this thread. Those sorts of answers are consistent or not, but they're not right or wrong.

If you find my post totally useless, just say so and I'll be on my way.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 15/09/2019 02:07:39
Quote from: Halc
If you find my post totally useless, just say so and I'll be on my way.

On the contrary; I find your answers interesting and informative.  I really appreciate the time and effort you devote to addressing my foibles.  In the same way that one might pass a humorous remark to/about a friend, that one would not pass about a relative stranger; I would not have made a joke about someone whose input I didn’t value.  I look forward to returning to more points from your contributions, and hope I have not put you off responding.


Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 15/09/2019 02:43:42
I liked the joke.

My reply was not totally in jest.  While some of the fallacies in thinking were pointed out, in the end the answer I gave is merely one I find consistent and relatively lacking in problems (like something coming from nothing).  But it was meant as a real disclaimer: I lay no claim that there are not other very different answers to the problems. I've just never found any others that worked as well.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 15/09/2019 17:10:44
Quote from: Halc
Well, my answer is not absolutely right, since it's philosophy, not physics, being discussed. You've been asking philosophical questions in this thread. Those sorts of answers are consistent or not, but they're not right or wrong.

You have a knack of putting a finger on problems.  Most people seem to regard this type of discussion as philosophical, and often dismiss it, as a result. (Thanks for not doing that). However, I have to wonder if looking for the possible origin of the Universe is, actually, philosophy.  Consider two questions.
 
1. Why is there something, rather than nothing?

2.  How can there be something, rather than nothing?

Sean Carroll asked Q1, and attempted a “physical” answer; but I would consider this to be philosophy.

Q2, on the other hand, asks for a “mechanism that would explain the obvious existence of “something”.  Surely, this is physics.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: RobC on 15/09/2019 18:40:29
Sidney Morgenbesser, his professor at Columbia, said to Jim Holt "even if there was nothing you still would not be satisfied".
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 16/09/2019 00:36:40
I have to wonder if looking for the possible origin of the Universe is, actually, philosophy.  Consider two questions.
 
1. Why is there something, rather than nothing?

2.  How can there be something, rather than nothing?

Sean Carroll asked Q1, and attempted a “physical” answer; but I would consider this to be philosophy.

Q2, on the other hand, asks for a “mechanism that would explain the obvious existence of “something”.  Surely, this is physics.
Your two question seem like the same thing to me.  Maybe I parse it differently.
I'd like to see Carroll's response to it if you have a link.  He usually does more of the physics answer: the mechanism behind what prompted the big bang. I have very little understanding of the various theories involved, and without a unified field theory, no real guidance as to which of them actually makes sense.  The all seem to have in common some greater field out of which separate bubbles of spacetime emerge, our own (that which started at the big bang) being one of them.

All these theories aside, none of them address the question of how/why there is something in the first place. It's a realist question, and a serious fault in realism because there never seems to be a satisfactory answer to it. Positing a god doesn't help at all since no god can create the cosmos, since the cosmos is everything, including the god. The deity answer is a realist one, and suffers the same problem as any realist position. For this reason, I abandoned realism some time back.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 16/09/2019 03:07:19
Why answers questions about reason. How answers questions about mechanism/method.

Consider: "How are cars built?" and "Why are cars built?"

Link to Sean's article:

 https://www.preposterousuniverse.com/blog/2018/02/08/why-is-there-something-rather-than-nothing-2/
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 16/09/2019 13:02:33
Why answers questions about reason. How answers questions about mechanism/method.

Consider: "How are cars built?" and "Why are cars built?"

Link to Sean's article:

 https://www.preposterousuniverse.com/blog/2018/02/08/why-is-there-something-rather-than-nothing-2/
He answers the physics question of the mechanism of the origin of the big bang, and only to say there is one, and to say it is a metaphysical mistake to use language that assumes a defined arrow of time when speaking of the physics outside our spacetime.

I see zero comments in that article that address the title.  He discusses the 'origin' of our universe, but not of what you're calling the cosmos.  He says it is a mistake to take our local experience of an arrow of time (what he calls 'metaphysical baggage') into the realm from which the big bang emerged, so there is no meaningful direction that is towards the 'beginning' of it, hence no obvious cause-effect relationship between two states, and hence no obvious first event that lacks a cause.  I agree with all that.  But none of it explains the existence of the structure in the first place vs the lack of its existence.  That's the part I think we're discussing.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 16/09/2019 14:40:18
"Why" presumes, or at least looks for, an ulterior motive or primary driver outside of the action being observed. When that action is "everything we can observe", you clearly aren't going to find a cause.

However everything we can observe, i.e. the Observable Universe, is not necessarily everything there is. Schwarzchild places a limit on the radius of the observable part of the universe, but not on everything that might exist.

Now we have two competing gravitational phenomena. At shortish distances, stuff tends to coalesce into galaxies and so forth, but if the universe is actually infinite, the stuff outside our observable radius is pulling the fringes outwards whilst the stuff inside is condensing into discrete chunks. So whilst the OU in its present form of accreting masses may well have begun with a big bang, that itself may have been caused by the coalescence of a previous OU into a black hole that was unstable in the gravitational field of everything else, or collided with another giant black hole.

So here's a difference between science and religion. I'm pretty sure there is stuff out there that I can't observe, but has played a part in my history and will play a part in my future, but I don't ascribe any motives to it, only a presumption that it behaves pretty much in the same way as the stuff I can see until proven otherwise. That's science, and in this case it suggests "how". 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 16/09/2019 18:28:57
Quote from: Halc
He says it is a mistake to take our local experience of an arrow of time (what he calls 'metaphysical baggage') into the realm from which the big bang emerged,

I’m not comfortable with calling our experience of time “metaphysical baggage” but “who am I to blow against the wind?”  However, extrapolating it to argue that there was time before the BB can lead to problems.

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  so there is no meaningful direction that is towards the 'beginning' of it, hence no obvious cause-effect relationship between two states, and hence no obvious first event that lacks a cause.

 I, too, agree with that; but it needs some qualifying if it is to explain the existence of the Universe. 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 16/09/2019 20:07:16
I’m not comfortable with calling our experience of time “metaphysical baggage” but “who am I to blow against the wind?”  However, extrapolating it to argue that there was time before the BB can lead to problems.
You cannot use comfortable terms to describe something that completely different than the environment in which we find ourselves.  Yes, there is time of sorts (possibly more than one dimension of it) outside the BB, but it isn't 'ordered' like it is here, so there is no 'before' and 'after' relation between events, and asking how it 'started' implies an ordering that is not there, and also a bound that has no reason to be there either.

I lay no claim to knowledge about that realm since such knowledge doesn't help answer the main problem I see.  My thinking is simpler than that.

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but it needs some qualifying if it is to explain the existence of the Universe.
That answer isn't found in there, which is why I've not explored it in depth.  Carroll did not answer the question in his title.  He just said there wasn't an obvious 'first cause' way over at one end that needs to be explained.  The whole thing needs to be explained, and he's right about that.  But he didn't actually address the question.

I reduced the question to 'why is the <cosmos> real?', and found no answer anywhere.  I thus abandoned my realist philosophy that I had held for quite some time. There are better alternatives.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 17/09/2019 01:34:53
Quote from: Alan
That's science, and in this case it suggests "how".

Agreed.  How would you be with extending that to saying that studying the contents/structure of the OU, in an attempt to adduce its provenance, would be “science”?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 17/09/2019 02:21:38
... studying the contents/structure of the OU, in an attempt to adduce its provenance
That part is figured out.  The BB represents said provenance of said OU, and plenty more that's not observable.

I'm pretty sure there is stuff out there that I can't observe, but has played a part in my history and will play a part in my future, but I don't ascribe any motives to it, only a presumption that it behaves pretty much in the same way as the stuff I can see until proven otherwise.
This is true for stuff too distant to observe.  Were you to observe it, it would appear/behave pretty much like it does here.  There is little to no reason this should be true outside our bubble of spacetime.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 17/09/2019 13:55:07
“There is nothing new to be discovered in physics now.”  Attributed (possibly apocryphally) to Lord Kelvin.

“.........the laws of physics underlying everyday life are completely understood.”  Sean Carroll.

“That part is figured out.”  Halc.

Eat your heart out, Nostradamus!  :)
 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 17/09/2019 14:05:24
Seriously, though: the laws of physics take us back to a fraction of a second after the BB; maths provides us with our best tool for understanding these laws; but, unless I’ve missed something vital, neither actually tells us how we could we can be here.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 17/09/2019 14:57:40
The presumption, as Halc says, is that the unobservable part of the universe (i.e. pretty much all of it) behaves the same as the observable part. Then by any reasonable definition of "infinite", the Big Bang and all its trivial and evanescent consequences (including us) was just one inevitable incident in a conservative continuum.

Or to put it simply, we're here because we are.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 17/09/2019 16:34:05
Quote from: Alan
Then by any reasonable definition of "infinite", the Big Bang and all its trivial and evanescent consequences (including us) was just one inevitable incident in a conservative continuum.

That’s fine, but it doesn’t address the question of how the “continuum” could exist. 

Is there a law of physics that says: there must always have been “something?
If so, is there a law that says it must be a continuum?
If so, is there a law that deals, effectively, with infinite regression?

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Or to put it simply, we're here because we are.

Straightforward statement of the Anthropomorphic Principle, but still misses the main point.

Stay with me, Alan (& Halc), there could be light on the horizon.

That’s not detracting from the valuable input of others, but Halc & Alan look like staying the course.  Brave!
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 17/09/2019 18:22:32
The laws of physics are simply the mathematical relationships we discover that rationalise what we know and predict what we might see. I don't see any disjoint between an infinite and fundamentally unchanging universe with occasional hiccups, and the laws that we have invented to describe our present hiccup.

"We're here because we are" is surely the diametric opposite of the anthropic principle, which states that everything else is there in order for us to be here. Seeing the universe, or even this tiny corner of it,  as constructed for Man, is vanity. Seeing  Man as a transient blip in the universe, is science. Remember that Goldilocks invaded  the Three Bears' house, which was actually built for the bears, not G-lox.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 17/09/2019 19:23:24
Quote
"We're here because we are" is surely the diametric opposite of the anthropic principle, which states that everything else is there in order for us to be here.

I was thinking of the “weak” version, which simply holds that the current Universe must be as it is to allow the existence of intelligent observers. IMO, the “strong” version is thinly disguised theology.

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I don't see any disjoint between an infinite and fundamentally unchanging universe with occasional hiccups,
 

This must depend on what you mean by “fundamentally”.  If you mean that an infinite universe is usually unchanging, but not always, I have a serious problem with that. 

If you mean that “unchangingness” is an essential feature of the universe; then, how can “hiccups” occur?

I agree, entirely, with the rest of #79.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 17/09/2019 19:41:09
That’s fine, but it doesn’t address the question of how the “continuum” could exist.
I understand what you're asking, and no, none of the immediate above discussion touches on it.  Physics is not in the business of answering such things.

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Is there a law of physics that says: there must always have been “something?
No, not at all. It's just not a physics/science question, despite all the diversions in that direction for the last several posts. The answer needs to be compatible with physics, but it isn't going to come from there. Try logic instead.

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Straightforward statement of the Anthropomorphic Principle, but still misses the main point.
Anthropic principle (weak) explains why the tuning is so nice (refuting teleological argument), but it has nothing to do with why there is something.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 17/09/2019 20:08:39
Quote
I understand what you're asking, and no, none of the immediate above discussion touches on it.  Physics is not in

It sounds as though you are saying that physics studies the Universe/cosmos, but is not interested in looking at any possible mechanism that might explain the existence of the Universe/cosmos. 

That seems a bit like studying the internal combustion engine, but refusing to consider manufacturing issues. 

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Anthropic principle (weak) explains why the tuning is so nice (refuting teleological argument), but it has nothing to do with why there is something.

Point taken.  I could agree, entirely, if you changed the second “why” to “how”.  Never did really like the AP.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 17/09/2019 22:48:48
If you mean that “unchangingness” is an essential feature of the universe; then, how can “hiccups” occur?
Long term, a bucket of water is a bucket of water, but we can detect transient local order with the formation of various polymers and voronoi polyhedra. https://en.wikipedia.org/wiki/Voronoi_diagram  is the seed of an idea about evanescent order in an infinite universe, but I haven't developed it formally.

You can also get some insight from Hawking's "Black holes and baby universes" where local creation and re-creation occur in an infinite matrix of bits of stuff.

If you like the idea of every particle having an antiparticle then you can imagine the instantaneous creation ex nihilo of a universe and its effective mirror image with a sum energy of zero, but these are more exotic than "everyday" antiparticles because for a zero sum, they must have negative mass. Let's call them negaticles. Where does that take us? Intriguingly, if two particles with positive mass are gravitationally attracted to one another (experimental observation!) then we might expect a particle and a negaticle to repel (hypothesis). Perhaps what is causing the expansion of the observable universe is the intervening negaticles, which themselves are clumping together.... So we can devise an OU with a beginning and possibly an end, derived instantaneously from nothing at all. Mad speculation, but remember you read it here first, and it is in principle open to investigation (science)!
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 18/09/2019 01:04:02
Quote
I understand what you're asking, and no, none of the immediate above discussion touches on it.  Physics is not in
I finished that sentence in an edit above.

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It sounds as though you are saying that physics studies the Universe/cosmos, but is not interested in looking at any possible mechanism that might explain the existence of the Universe/cosmos.
There can't be a 'mechanism'.  If there was one (like Carroll is describing a mechanism for our big bang), then it is part of the cosmos, and needs to explain itself. That's the problem with saying God did it. Doesn't explain why there is a god and not no-god. It doesn't matter if the 'cosmos' had some sort of edge that can be designated as 'first', or it 'was always there', Neither case explains its existence vs its nonexistence.

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That seems a bit like studying the internal combustion engine, but refusing to consider manufacturing issues.
That's a physics question.  What caused this internal combusion engine?  Such a thing is an object, not a cosmos, and objects have creation mechanisms that are separate from the object.  I have such a mechanism.  The cosmos cannot, by definition.

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I could agree, entirely, if you changed the second “why” to “how”.  Never did really like the AP.
Don't care what work you choose.  I said I know what you're asking.

If find that most questions like that are begging a set of biases, and the first thing is to identify those biases.
For instance, the second big question that drove me nuts for years was "Why am I me".  It also was begging an assumption that there was an 'I' that sort of won a lottery and got to be something pretty awesome like 'me' and not something far more likely but lame like a bug or a dust mote.  That's a hard bias to drop, but the question wasn't baffling anymore once I did it.  The same process needs to take place with "why is there something".
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 18/09/2019 07:37:58
"The universe must be as it is to allow the existence of an intelligent observer" seems like a good summary of weak anthropism but it is frankly meaningless or vanity.

If the universe were not as it is, we would not be as we are, but there is no reason to dismiss the possibility of even a marginally different universe in which some Martian pointed his tentacle at the sky and said "I wonder what's going on up there? And why isn't that big planet with one moon blue and covered with octopus, like ours?" Indeed there is every reason to think it may have happened, when the universe was not as it is now. 

The alternative interpretation is an active rendering of "must be", suggesting that the diameter of the ninth planet from the third sun in Klingon Minor, 3 billion light years away, is critical to the evolution of life on earth, which is straining the credulity a bit, especially if you like the idea of a Creator who could just say "let there be light" and avoid all the complexities of physics and chemistry.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 18/09/2019 12:36:00
There’s some fascinating and educational stuff in this thread, the last three posts being good examples.  Just need the time to read them properly, and let the ideas percolate before I try to respond.

Just an aside: I’ve made numerous attempts to get this sort of discussion going; then along comes a first timer and hits the jackpot.  Thanks Akabiz, I hope you’re enjoying this. :)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 19/09/2019 15:01:44
Quote from: Alan
Long term, a bucket of water is a bucket of water, but we can detect transient local order with the formation of various polymers and voronoi polyhedra. https://en.wikipedia.org/wiki/Voronoi_diagram  is the seed of an idea about evanescent order in an infinite universe, but I haven't developed it formally.

Voronoi diagrams have come a long way since the identification of a source of cholera, and I don’t pretend to understand the maths, but “evanescent order in an infinite universe” is possible only if you treat infinity as a number.  Order requires separation and distinction. This is possible, only if infinity is divisible. How do you divide something that is not numerical? 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 19/09/2019 17:47:46
Quote from: Alan
If you like the idea of every particle having an antiparticle then you can imagine the instantaneous creation ex nihilo of a universe and its effective mirror image with a sum energy of zero,

My Latin may have been rusting for approaching 50 yrs, but I still think “ex nililo” means “from nothing”.   Wouldn’t you say that particles and antiparticles were “something”?  Don’t they have to exist in order to bring about this wondrous creation?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 19/09/2019 19:21:38
Quote from: Alan
If you like the idea of every particle having an antiparticle then you can imagine the instantaneous creation ex nihilo of a universe and its effective mirror image with a sum energy of zero,

My Latin may have been rusting for approaching 50 yrs, but I still think “ex nililo” means “from nothing”.   Wouldn’t you say that particles and antiparticles were “something”?  Don’t they have to exist in order to bring about this wondrous creation?
It also requires positive energy to create a particle/antiparticle pair.  Antimatter doesn't have negative energy.  Graviational potential energy is negative, which is why the big bang doesn't seem to violate energy conservation, but yes Bill, it still isn't something from nothing, even if the total sum of mass in the universe is zero.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 19/09/2019 22:37:55
I wasn't talking about conventional everyday antiparticles! Negaticles are hypothetical particles with negative mass but otherwise identical properties to normicles like electrons and positrons.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 19/09/2019 22:40:43
How do you divide something that is not numerical? 
We've discussed this elsewhere. A denumerable infinity already contains divisions, and an infinite continuum can be sliced as easily as any cake, but many more times.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 19/09/2019 23:24:01
I wasn't talking about conventional everyday antiparticles! Negaticles are hypothetical particles with negative mass but otherwise identical properties to normicles like electrons and positrons.
They have asymmetric properties with normal mass, so not identical.  Given a ball of each, one could tell which was which.  Given two identical masses exerting gravity on each other, both objects will accelerate in the direction of the positive mass.  I tried to follow the proof that this sort of thing violated conservation laws, but could not.  Reactionless thrust!  Anyway, perhaps there is a contradiction, but negative mass does indeed seem to be a valid solution to the equations.
A negative mass planet would not hold itself together by gravity, so a universe of it would hardly be a mirror of this one.

This topic deserves its own thread since there so much fun to it.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 23/09/2019 11:52:17
Lengthy threads, like this, are inclined to drift, then fizzle out without anyone even attempting to pull the ideas together.  The OP is probably the best person to do this, but I think I’ve hijacked the thread, and have certainly learned from it, so, hopefully Akabiz won’t mind if I try some “pulling together”.

I’m struggling to find time to stay in discussions, so am aiming for some sort of “resolution”.

Long posts tend to attract answers/comments relating to specific points, only, ignoring other, possibly relevant, points.  I’m going to try the “one step at a time” approach. 

First, three questions, with suggested answers; and an invitation to anyone who disagrees to say so/why.  I know these questions have been asked before and will probably be asked again, but, hopefully, not by me.

1. Is infinity a number? 
    No.

2. Is eternity a length of time? 
    No.

3. To what extent is infinity/eternity amenable to mathematical manipulation?   
    Only in so far as it can be manipulated in time.  E.g. An “infinite” sequence can be defined, and manipulated, only in the context of time. 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 23/09/2019 15:11:28
Lengthy threads, like this, are inclined to drift, then fizzle out without anyone even attempting to pull the ideas together.  The OP is probably the best person to do this, but I think I’ve hijacked the thread, and have certainly learned from it, so, hopefully Akabiz won’t mind if I try some “pulling together”.
Akabiz seems to have moved on.  It's kind of your discussion at this point.

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First, three questions, with suggested answers; and an invitation to anyone who disagrees to say so/why.  I know these questions have been asked before and will probably be asked again, but, hopefully, not by me.

1. Is infinity a number? 
    No.

2. Is eternity a length of time? 
    No.
Effectively the same question as #1.  'Eternal' has multiple meanings, only one of which is 'for all eternity', i.e. 'for an unbounded amount of time'.  I tend not to mean that when I use the term eternal.  I take the meaning from 'eternalism' which essentially 'outside of time'.

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3. To what extent is infinity/eternity amenable to mathematical manipulation?   
    Only in so far as it can be manipulated in time.  E.g. An “infinite” sequence can be defined, and manipulated, only in the context of time.
There is a lot of mathematics on the subject.  Just because you can't meaningfully add three to it doesn't mean it is not amenable to mathematical manipulation.  Hilbert's infinite hotel is a great example of the sort of manipulation that can be done in this area.

All that said, I find discussion of infinity to be off-track to a discussion of why not nothing.  Even those that posit infinite past (lack of first cause) have no explanation for its being there vs it not being there.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 23/09/2019 15:28:36
A negative mass planet would not hold itself together by gravity, so a universe of it would hardly be a mirror of this one.
Ah, but it would, since negative masses have negative gravity.  -1 x -1 = 1

My use of "identical" was a bit loose. What I meant was a complementary universe of negaleptons and negahadrons with charge, spin etc  the same as their observed counterparts, but with negative mass.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 23/09/2019 18:23:45
Quote from: Halc
  'Eternal' has multiple meanings, only one of which is 'for all eternity'…

Colloquial usage aside, what else could “eternal” mean?

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  i.e. 'for an unbounded amount of time'.

From the fact that you didn’t object to my answer to Q2, I assumed you agreed that eternity is not a length of time.  It seems my assumption was wrong.   Perhaps you would clarify this.

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I take the meaning from 'eternalism' which essentially 'outside of time'.

Could be I’m having a “senior moment”, but I am finding it hard to equate 'for an unbounded amount of time' with 'outside of time'.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 23/09/2019 19:40:22
A negative mass planet would not hold itself together by gravity, so a universe of it would hardly be a mirror of this one.
Ah, but it would, since negative masses have negative gravity.  -1 x -1 = 1
That function (F=GMm/r² for instance) computes force, not acceleration.  Yes, two negative masses exert positive (attraction) force on each other, but a negative mass accelerates in the opposite direction as the force applied to it.
F=ma, or a = F/m where F is positive but m and thus a are negative.  The physics of such a world would be quite different than the one we know, but I actually find it hard to identify a contradiction.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 25/09/2019 14:27:40
Just starting to pull some thought together, with obvious input from other posters.  I start with some of the problems of language.

Expressing the idea that there was never nothing is not as straightforward as it might seem at first glance.

Start with “there was never a time when there was nothing”, and reason that time is something, therefore, if there were nothing, any concept of time would be irrelevant.  This leaves: “There was never nothing”.
 
The past tense, implies a statement that there is not a time in which this “thing” did not exist, but if time is not part of infinity, it is meaningless to reference times in relation to the existence of the infinite cosmos.
Reasonable as that might be, “there is never nothing” seems distinctly odd.

Presumably, the true pedant would also take issue with “never”, on the grounds that it is an abbreviation of “not ever”, which implies passage of time.  Dispensing with “never” leaves us with “there is nothing”; which, manifestly, is not quite what is needed. 

Talking of a “mechanism” by which a finite universe might “emerge” from an infinite cosmos, is another minefield. If the cosmos is infinite/eternal, then no mechanism can operate in the cosmos, because there is no time in which any sort of operation can take place.

“Emerge” can also be cited as problematic.  The action of emergence involves change, and change requires time. 

All of these illustrate the ever-present language difficulty.  They also demonstrate the fact that it is very easy to adopt a pattern of thought that is so influenced by our, necessarily, 3+1D environment that it precludes a real appreciation of the infinite.

Perhaps the lesson to draw from this is that we have to make the best of our finite-based language, take care to be as precise as possible, and smile benignly at obfuscators. 

“You know what I mean, ‘Arry?” :)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 25/09/2019 15:05:54
Start with “there was never a time when there was nothing”, and reason that time is something, therefore, if there were nothing, any concept of time would be irrelevant.  This leaves: “There was never nothing”.
Without something to change, time would be meaningless.  If you picture a sort of external time that flows along despite the lack of anything to change, then you still have time existing, which is something.  So it seems that asserting the opposite, that there was a time when there was nothing, is self contradictory.
 
As a relativist (as opposed to a realist), I don't think it makes syntactic sense to say a thing exists or not.  It exists relative to something else.  That's what the word means.  It means something like 'is a member of'.  So 'why is there something?' becomes 'why is something a member of something else?".

I find it obfuscating to complicate any of that with temporal references.  Sure, thing X can be a member of temporal thing Y between moments of creation and destruction and not at other times, but that seems needlessly more complex than just saying X is a member of Y.  So I (my perceived worldline) exist in (relative to) this world, but I don't exist in 1920 (a subset of this world).  My worldline isn't that long.  Since I have a finite duration in the temporal set Y (what I call 'this world'), I am a created thing.

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Presumably, the true pedant would also take issue with “never”, on the grounds that it is an abbreviation of “not ever”, which implies passage of time.
Disagree. The word implies a temporal ordering, but not passage. It just means 'at no time' but gives no implied reference to a present moment or flow.  It is only a valid reference to a temporal object/set, so it doesn't make sense to say "In the set of integers, 5 is never greater than 7" since the set of integers is not a temporal set.

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Talking of a “mechanism” by which a finite universe might “emerge” from an infinite cosmos, is another minefield. If the cosmos is infinite/eternal, then no mechanism can operate in the cosmos, because there is no time in which any sort of operation can take place.
The cosmos contains time, not the other way around.  Thus things can emerge within it since there are times without the thing (1920) and times with the thing (1990).  Emerge means there was a time when it wasn't present, and a subsequent time when it was.  An eternal temporal structure still has time, it just doesn't exist within that time. Time exists within it.

Cellular automata is a great example of such a structure. A lot of my modelling is based on such simple examples.

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“Emerge” can also be cited as problematic.  The action of emergence involves change, and change requires time.
Exactly so.  The state of the world in 1920 is not the same as the state in 1990, so there is change over time.

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Perhaps the lesson to draw from this is that we have to make the best of our finite-based language, take care to be as precise as possible, and smile benignly at obfuscators.
I try my best.  If you find my language above sort of awkward in places, it's because I'm trying to be as precise as possible.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 25/09/2019 19:01:00
Yes, two negative masses exert positive (attraction) force on each other, but a negative mass accelerates in the opposite direction as the force applied to it.
So we can make a zero-energy universe by separating particles and negaticles in a big bang, and then the particles coalesce into atoms and galaxies, whilst the negaticles push them and themselves apart. Not bad, eh? We have an expanding observable universe driven by increasingly rareified unobservable dark negastuff which disperses along with the observable stuff, so it never stops expanding. All created ex nihilo and exactly as observed, with no need for an old man with a beard to make it happen.

Tomorrow, I think I'll fix Brexit, then explain the Marie Celeste after lunch.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 25/09/2019 19:32:08
Quote from: Halc
Without something to change, time would be meaningless.  If you picture a sort of external time that flows along despite the lack of anything to change, then you still have time existing, which is something.  So it seems that asserting the opposite, that there was a time when there was nothing, is self contradictory.

I think we agree, thus far.

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….. I don't think it makes syntactic sense to say a thing exists or not.  It exists relative to something else.  That's what the word means.

If the cosmos is infinite, and all that there is, there is nothing to which its existence can be relative.  By your definition, therefore, it doesn’t exist.  (?) 

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The word implies a temporal ordering, but not passage.

 
Quote from: https://www.google.com/search?q=never&oq=never&aqs=chrome..69i57.9317300j0j1&sourceid=chrome&ie=UTF-8
1. at no time in the past or future; not ever.

Perhaps life would be simpler if every word had a universally accepted definition, but the “inner poet” says: Boring!

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The cosmos contains time, not the other way around.

Where did I say that the cosmos is contained in time?  If I gave that impression, it was unintentional. 

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An eternal temporal structure still has time, it just doesn't exist within that time. Time exists within it.

Am I mis-interpreting this, or does it say that eternity is a length of time?

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I try my best.  If you find my language above sort of awkward in places, it's because I'm trying to be as precise as possible.

I’m sorry if you took my comment personally, it was certainly not meant that way.  As far as language goes, I’m always happy to have my usage challenged. How else does one continue learning?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 25/09/2019 19:42:09
Quote from: Alan
Tomorrow, I think I'll fix Brexit, then explain the Marie Celeste after lunch.

What's the betting that you will find the crew of the Marie Celeste before you find those negative masses?
Fix Brexit!  Can I borrow your magic wand when you've done that?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 25/09/2019 23:15:30
Funnily enough, Parliament fixed Brexit three years ago.

Having agreed to abide by the result of the referendum, they then enacted a single law that preserved all existing laws and regulations until such time as they were individually amended or abolished. Thus we could have left the EU the next day, with no change in import tariffs, citizenship, or anything, and simply tweaked the regulations from time to time as the need or opportunity arose. This would have restored the sovereignty of parliament at a stroke, with negligible initial impact on anyone's life and no urgency to reform anything. In the event that the EU  imposed any unreasonable tariff on UK exports, it was entirely in the government's power to immediately ban the import of finished cars and thus destroy the euro (as the EU has just discovered this week), so any trade deals or reformed tariff structures could evolve ad hoc, with the UK negotiating from a position of strength.

Legal or not, BJ's prorogation would have ended the embarrassing and damaging party political sideshow and enacted the will of the majority without harm to anyone or anything (especially sterling). Who knows, Thomas Cook might have been able to pay its bills!

Relevance? Well, it helps to put some numbers to the problem. The number of negaticles that can fit on the head of a pin  cannot be less than the number of truly honorable members of parliament.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 26/09/2019 00:09:56

Quote from: Halc
I don't think it makes syntactic sense to say a thing exists or not.  It exists relative to something else.  That's what the word means.
If the cosmos is infinite, and all that there is, there is nothing to which its existence can be relative.  By your definition, therefore, it doesn’t exist.  (?) 
By my definition, saying it doesn't exist isn't a syntactically valid statement.  "The cosmos is not a member of."  Incomplete statement.  So no, I'm not saying that, and my definition has nothing to do with the set being infinite or not.  It works with the cosmos being finite as well.

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Quote
The word ['never'] implies a temporal ordering, but not passage.
Quote from: https://www.google.com/search?q=never&oq=never&aqs=chrome..69i57.9317300j0j1&sourceid=chrome&ie=UTF-8
1. at no time in the past or future; not ever.
That particular quote does reference a present, yes. It doesn't need to.

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Perhaps life would be simpler if every word had a universally accepted definition, but the “inner poet” says: Boring!
Then we'd need to make up new words for discussions like this since I'm not using everyday definitions of most terms here.

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The cosmos contains time, not the other way around.
Where did I say that the cosmos is contained in time?  If I gave that impression, it was unintentional.
Any suggestion of the universe being a created thing puts the created thing in time instead of the other way around that physics puts it.  Doesn't mean there isn't time outside the universe, but it isn't the time we know (measured in seconds and having an obvious direction to it).

Anyway, I said that because you said nothing can emerge in the universe, which is only true if there was no time, but there is.  Emergence of something is its presence at one time and lack of presence at a prior time.  The word implies an ordering, yes.  If there is no arrow, then there may be a thing during a finite span of time, but at neither end does it 'emerge' or 'disappear' since neither end is the obvious beginning or end to it.

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An eternal temporal structure still has time, it just doesn't exist within that time. Time exists within it.
Am I mis-interpreting this, or does it say that eternity is a length of time?
I didn't say eternity.  I said eternal structure, which is a structure with a temporal component (a structure that contains time), be the time dimension finite or infinite.  Infinite (unbounded) time is eternity.  We've no solid evidence that our time is not bounded at either end, so it is unclear if our universe has an eternity of time.  OK, it appears bounded in the 'past' direction, but that's just 'time as we know it'.

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I try my best.  If you find my language above sort of awkward in places, it's because I'm trying to be as precise as possible.
I’m sorry if you took my comment personally, it was certainly not meant that way.  As far as language goes, I’m always happy to have my usage challenged. How else does one continue learning?
I took nothing personally.  I had to say that because I want it clear that I'm trying to be as precise as I can. I'm not quoting somebody else's work here. I've not found a good reference to what I'm describing, which is sort of the extension of the relation interpretaton of QM (RQM, initially Rovelli, 1994) to cosmology and philosophy of mind.

I do my best to identify and question all biases I seem to hold, but some I am unable to give up.  Foremost, I reject any anthropocentric view of things.  If that's true, almost all of observation could be a lie and we've nothing empirical to go on.  Oddly enough, RQM replaces realism with a sort of non-mental idealism, which avoids all the solipsism that arises from a mind-realism view like philosophical idealism, which has other serious issues.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 26/09/2019 17:11:02
Quote from: Halc
By my definition, saying it doesn't exist isn't a syntactically valid statement.  "The cosmos is not a member of."  Incomplete statement.  So no, I'm not saying that, and my definition has nothing to do with the set being infinite or not.  It works with the cosmos being finite as well.

Your definition appears to imply that I am claiming that “The cosmos is not a member of." Something.  I make
no such claim. 

If you defend your position in terms of syntax, perhaps we should check your definition of “syntactically". I would define it as relating to the grammatical arrangement of words in a sentence.

I would define “exists” as, to have objective reality or being.

I lack the syntactical elasticity to convert “exists” into “is a member of”. 

Alan said at Re: Do we go round in circles?

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Infinity exists in the same way that God exists: it is a word that we use as we wish, to convey whatever is appropriate in context.

Yes we do go round in circles, and will continue to do so as long as we accept “ Humpty Dumpty” linguistics.
 
Quote from: Halc
Anyway, I said that because you said nothing can emerge in the universe,

Where did I say that?

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.  If there is no arrow, then there may be a thing during a finite span of time, but at neither end does it 'emerge' or 'disappear' since neither end is the obvious beginning or end to it

How do you define time that has no arrow?  What would be a “finite span” of such time? 

I know there’s more in your post, but I’m out of time.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 26/09/2019 19:33:15
Quote from: Halc
I didn't say eternity.  I said eternal structure, which is a structure with a temporal component …. Infinite (unbounded) time is eternity.
 

You distinguish between “eternity” and “eternal structure”.  Before we can look further at this we would need to know if you agree that eternity is not a length of time. 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 27/09/2019 05:11:17
Quote from: Halc
By my definition, saying it doesn't exist isn't a syntactically valid statement.  "The cosmos is not a member of."  Incomplete statement.  So no, I'm not saying that, and my definition has nothing to do with the set being infinite or not.  It works with the cosmos being finite as well.
Your definition appears to imply that I am claiming that “The cosmos is not a member of." Something.  I make
no such claim. 
I know you made no such claim.  You're using a different definition of 'exist' when asking your question.  I'm saying the question goes away with my definition.

Platonic realism says that something like the number 13 (not the symbol or an instance, but 13 itself) exists.  A non-realist for number would say that abstract things like that are not real.  Using a relational definition of 'exist', I merely assert that 13 is an integer (more formally: 13 is a member of the set of integers), and asking how 13 comes to be real or not real are both meaningless queries since neither meaningless claim is made.

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I would define “exists” as, to have objective reality or being.
Right.  I define it differently.  We can use a different word if it helps, but the RQM view is not one of an objective reality, so nothing is a member of it.. Your definition leads to the unanswerable question of 'why does objective reality have something instead of not'. The relational view does not posit an objective reality that may or may not have anything.

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Infinity exists in the same way that God exists: it is a word that we use as we wish, to convey whatever is appropriate in context.
Yes we do go round in circles, and will continue to do so as long as we accept “ Humpty Dumpty” linguistics.
Don't know where you got that quote since it doesn't come from anywhere in this topic. It isn't mine.
 
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Quote from: Halc
Anyway, I said that because you said nothing can emerge in the universe,
Where did I say that?
Post 98 where you said "Talking of a “mechanism” by which a finite universe might “emerge” from an infinite cosmos, is another minefield. If the cosmos is infinite/eternal, then no mechanism can operate in the cosmos, because there is no time in which any sort of operation can take place."

You said cosmos, not universe.

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.  If there is no arrow, then there may be a thing during a finite span of time, but at neither end does it 'emerge' or 'disappear' since neither end is the obvious beginning or end to it
How do you define time that has no arrow?
Same as regular time, but no obvious direction that is past or future, or cause and effect.  Still measured in something regular like seconds or something, assuming something regular is going on.
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What would be a “finite span” of such time?
A finite span means it is terminated somewhere.  I personally think our time is finite in both directions (BB at one end, Big rip at the other), but it could also just fade away in heat death.  That's still an end to time of sorts because the direction is gone, and so is change and regularity.  There would be nothing to define a second anymore.  How is that not the end of time?  So our time seem finite in both directions, or seems to to me.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 28/09/2019 13:18:23
Quote from: Halc
Don't know where you got that quote since it doesn't come from anywhere in this topic. It isn't mine.

https://www.thenakedscientists.com/forum/index.php?topic=76446.0      #8
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 28/09/2019 13:40:33
Quote from: Halc
Don't know where you got that quote since it doesn't come from anywhere in this topic. It isn't mine.
https://www.thenakedscientists.com/forum/index.php?topic=76446.0      #8
OK, It's an Alan quote.  You even said that when you posted it.  I just didn't catch that connection.

Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 28/09/2019 13:42:49
Let’s look at two definitions of eternity.

1. Infinite or unending time.

2. A state to which time has no application; timelessness.

At first glance, these appear contradictory, but, “common usage by educated people” demonstrates that both are useful definitions, in different contexts.  Would you agree with that?

Could it be that differentiating between “eternity” and “eternal structure” conflates the two contexts?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 28/09/2019 14:33:16
Let’s look at two definitions of eternity.

1. Infinite or unending time.

2. A state to which time has no application; timelessness.

At first glance, these appear contradictory, but, “common usage by educated people” demonstrates that both are useful definitions, in different contexts.  Would you agree with that?
Of course.  Didn't say otherwise.  But those are different meanings, and if ambiguous, it should be made clear which is meant in a statement.

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Could it be that differentiating between “eternity” and “eternal structure” conflates the two contexts?
I've used the latter term, by which I mean a structure whose existence is not relative to time.  It does not mean it isn't a temporal structure (one containing time).

So for instance the Mandlebrot set is an eternal structure, but not a temporal one.  It is essentially a 1 dimensional map in the complex plane.
This image depicts a cellular automata that's a nice example of a simple temporal eternal structure:
https://dsweb.siam.org/Portals/DSWeb/EasyDNNnews/1510/1510pi_pa_000001623.jpg

The set of all valid chess states is a wonderful example of a temporal eternal structure with a sort of Hilbert space, much like our own universe.  I've used that example on a number of occasions.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 28/09/2019 17:19:09
Quote from: Halc
Platonic realism says that something like the number 13 (not the symbol or an instance, but 13 itself) exists.  A non-realist for number would say that abstract things like that are not real.  Using a relational definition of 'exist', I merely assert that 13 is an integer (more formally: 13 is a member of the set of integers), and asking how 13 comes to be real or not real are both meaningless queries since neither meaningless claim is made.

Good sound philosophical thinking; but as one who tends towards pragmatism, I would say that “13” is a mathematical concept and “exists” as such.  Anyone who needs or wishes to explore to greater depths is welcome to do so. Given more time, I might enjoy joining in.   
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 28/09/2019 17:48:05
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Of course.  Didn't say otherwise.

Just checking.  My memory being what it is, I have to guard against quoting others as saying thing they didn’t say. :)

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  I've used the latter term, by which I mean a structure whose existence is not relative to time.  It does not mean it isn't a temporal structure (one containing time).

I see the distinction, but could you give an example, please.  I appreciate that you have given an example, at

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The set of all valid chess states is a wonderful example of a temporal eternal structure

But I’m not clear as to how that is “eternal”.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 28/09/2019 21:53:18
Good sound philosophical thinking; but as one who tends towards pragmatism, I would say that “13” is a mathematical concept and “exists” as such.  Anyone who needs or wishes to explore to greater depths is welcome to do so. Given more time, I might enjoy joining in.
I don't want to drop this because it's important. I balk at the word 'concept' because that implies that mathematical are products of say human minds and thus we created 13.  But the universe seems to be fundamentally a mathematical structure and thus would not have existed without humans or somebody to create the mathematics upon which it depends.  I'm a relativist, not an idealist, despite some disturbing similarities between the two.

The particle physicists try to figure out what exactly is real: A quark or a photon or something, but quantum mechanics seems not to support the actual existence of something like matter.  All they find is mathematics (wave function in particular).  They find actual mathematics, and not just mathematical concepts.

That said, 13 is an element of the eternal set of integers.  That set isn't a created thing, so it isn't applicable to discuss the time in which it exists.  It is eternal by definition 2 in your post.

Ditto for the other objects I mentioned.

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I've used the latter term, by which I mean a structure whose existence is not relative to time.  It does not mean it isn't a temporal structure (one containing time).

I see the distinction, but could you give an example, please.
The Mandlebrot set is not temporal.  It's merely a map of which complex numbers have a certain property and which do not.  There's nothing that evolves over time.
The automata (the linked image) definitely has time in it.  Time is vertical, going downward, and each state (horizontal row of pixels) can be determined from (caused by) the row immediately above it.  That example is 100% deterministic, a really simple structure.
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But I’m not clear as to how that is “eternal”.
They're all eternal in that all are abstract mathematical sets which are discovered, not created.  The chess thing is arguably not eternal because it really is a product of a human concept, but the same rules might be chosen by an alien independently, and if they do, they'd define the exact same set.

The set of all valid chess states is temporal and even has entropy.  It has a time zero (the initial state) and a count of half-moves since that point.  The structure has a fixed (finite) number of states since the max game is something like 10000 half-moves.  In that sense it is deterministic, but in other senses it is not.  From the initial state, one cannot ask the fate of the white queen since that cannot be determined from the initial state.  It cannot be determined except from a state where there is no white queen, or from one of the end states.  From any other state, a 'wave function' best describes the potential fates of the queen.  It is a bit like multiworld interpretation in that sense, but MWI's realist stance contains what I feel is its fatal flaw.
There is no current state in the chess structure.  If there was, it wouldn't be eternal because it would represent a game being played, and that is a created structure.  The set of all valid chess states does not involve the game being played.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: cleanair on 28/09/2019 23:36:42
Sean Carroll believes the universe is infinite in both directions i.e. it never had a beginning, it was always there and it will never end.

It may be interesting to look at the Horizon Problem.

The Horizon Problem

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In our hu-man words, this means 13.8 billion light-years in all directions, the Universe doesn't repeat. Light has been travelling towards us for 13.8 billion years this way, and 13.8 billion years that way, and 13.8 billion years that way; and that's just when the light left those regions. The expansion of the Universe has carried them from 47.5 billion light years away. Based on this, our Universe is 93 billion light-years across and earth is in the exact middle of the Universe.

If we look far out into space, billions of light years away, we see photons with the same temperature -- roughly 2.725 degrees Kelvin. If we look in another direction, we find the same thing. What a coincidence! In fact, when astronomers look in all directions, no matter how distant, they find that all regions have the same temperature. This is incredibly puzzling, Siegel says, "since these regions are separated by distances that are greater than any signal, even light, could have traveled in the time since the Universe was born.

Sources:
https://www.realclearscience.com/blog/2016/05/three_problems_with_the_big_bang.html
https://phys.org/news/2015-03-universe-finite-infinite.html

Inflation theory is invented to make the Big Bang theory plausible again, however, some scientists are complaining that it's practically a religion and one of the co-founders recently turned his back on the idea.

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1) The Monopole Problem
2) The Flatness Problem
3) The Horizon Problem

You will find the above three problems religiously repeated as a motivation for inflation, in lectures and textbooks and popular science pages all over the place.

Source: Sabine Hossenfelder, theoretical physicist specialized in quantum gravity and high energy physics.

One of inflation’s cofounders has turned his back on the idea. But practically no one else is following him. Is he right?

I was dismayed to see that the criticism by Steinhardt, Ijas, and Loeb that inflation is not a scientific theory, was dismissed so quickly by a community which has become too comfortable with itself.

There’s no warning sign you when you cross the border between science and blabla-land. But inflationary model building left behind reasonable scientific speculation long ago. I, for one, am glad that at least some people are speaking out about it. And that’s why I approve of the Steinhardt et al. criticism.

The Big Bang theory was originally named Cosmic Egg theory.

The following article may be of interest as well:

Einstein’s Lost Theory Describes a Universe Without a Big Bang

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Einstein and most scientists held that the universe was “simply there” with no beginning or end. But it’s interesting to note that creation myths across cultures tell the opposite story. Traditions of Chinese, Indian, pre-Colombian, and African cultures, as well as the biblical book of Genesis, all describe (clearly in allegorical terms) a distinct beginning to the universe—whether it’s the “creation in six days” of Genesis or the “Cosmic Egg” of the ancient Indian text the Rig Veda.

http://blogs.discovermagazine.com/crux/2014/03/07/einsteins-lost-theory-describes-a-universe-without-a-big-bang/
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 29/09/2019 11:58:46
quantum mechanics seems not to support the actual existence of something like matter.  All they find is mathematics (wave function in particular).  They find actual mathematics, and not just mathematical concepts.
Not happy with that. QM is an attempt to produce a mathematical model of what is observed. It can't "find" anything but might just predict what we do find. It works nicely for molecular structures where it is highly predictive, but seems to be continually catching up with subatomic particles. 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 29/09/2019 20:54:38
Not happy with that. QM is an attempt to produce a mathematical model of what is observed. It can't "find" anything but might just predict what we do find.
I'm not saying that QM can or cannot find anything.  I'm saying that the closer a scientist looks at matter, the less it looks like matter with properties like volume or coordinates or anything.  It's the empirical tests that cannot find actual matter.

Anyway, I'm not asserting that say an electron isn't real.  I'm interpreting the findings that way.  If you assert that it is real (has an objective state, independent of knowledge or measurement of it), then one has to accept that I can cause an effect in the past, and not just a little.  All interpretations that assert the measurement-independent reality of things need to discard locality which asserts my choices cannot have effects outside my future light cone.
I personally find the latter more offensive, hence I prefer an interpretation that supports locality, and none of them support a measurement-independent state of things.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Razza on 30/09/2019 07:05:13
Theoretical universes come in a menagerie of shapes and clocks.
Our one-verse aka universe could be part of a variety of multi-verses which theoretically result from other independent big bang and quantum events.
These theoretical universes are named parallel, bubble, oscillating, Smolin Fecund, elementary quark, quilted, Brane, cyclic, landscape, quantum, holographic, and ultimate etc. universes. Also, there are amidst the circus, numerical binary universes and some metaphysical antiverses, etc.,  etc.,
The new kid in town is 'Bi-verse the cosmic split'
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 04/10/2019 21:53:32
Quote from: Halc
That said, 13 is an element of the eternal set of integers………  It is eternal by definition 2 in your post.

Quote from: Bill
2. A state to which time has no application; timelessness.

Just have a few minutes to try to pick up this thread again.

The set of integers might be “eternal” by definition 1, but it has relevance only in terms of a “finite reality”.
By definition 2, there is no concept of change, therefore it is meaningless to talk of a set of anything, as this involves differentiation, which requires change.  Change requires time, and by definition 2, eternity is timeless.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 05/10/2019 07:15:05
The set of integers might be “eternal” by definition 1, but it has relevance only in terms of a “finite reality”.
Not sure what you mean by 'finite reality'.  The set of integers is not a finite set.

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By definition 2, there is no concept of change, therefore it is meaningless to talk of a set of anything, as this involves differentiation, which requires change.  Change requires time, and by definition 2, eternity is timeless.
There are plenty of sets that don't involve change.  Yes, integers, or the Mandlebrot set are examples.
The set of valid chess states is an example (a finite one) that involves time and change, yet is an eternal structure by definition 2.  That designation is kind of thin since chess is arguably a created thing and exists in our time as well as containing its own time.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 05/10/2019 21:57:11
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Not sure what you mean by 'finite reality'.

That in which we perceive ourselves to be existing.

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The set of integers is not a finite set.

By Def. 1, that is true, but by Def. 2, it is not.

Possibly Def. 2 needs rewording so as to make it less susceptible to “invasions” from Def. 1.

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There are plenty of sets that don't involve change.  Yes, integers, or the Mandlebrot set are examples.
The set of valid chess states is an example (a finite one) that involves time and change, yet is an eternal structure by definition 2.

By Def. 2, eternity is timeless.  Any differentiation between parts would involve the input of an external observer who existed in time.  To be clear, I’m not saying (at this point) that a set or sequence could not exist in eternity; only that by Def. 2 it would be meaningless.
 
How can a set, or sequence, of anything have any meaning if it is not possible to consider individual members independently?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 06/10/2019 14:42:50
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Not sure what you mean by 'finite reality'.
That in which we perceive ourselves to be existing.
So your statement means "The set of integers might be “eternal” by definition 1, but it has relevance only in terms of the reality in which we perceive ourselves to be existing."
I must disagree with that.  A different reality would also find integers relevant, although not necessarily all realities.
As I said, I have an inherent bias against anthropocentric views.

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The set of integers is not a finite set.
By Def. 1, that is true, but by Def. 2, it is not.
I don't see any mention in either def about a thing itself being finite or not.  Def 1 talks about time being infinite, but the set of integers is not a temporal structure.  It has no time at all, let alone finite or infinite time.

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There are plenty of sets that don't involve change.  Yes, integers, or the Mandlebrot set are examples.
The set of valid chess states is an example (a finite one) that involves time and change, yet is an eternal structure by definition 2.

By Def. 2, eternity is timeless.[/quote]Depends on what you mean by timeless.  A timeless structure does not exist within time, but time can still exist within it.  The chess example and our 'cosmos' are both such examples of timeless temporal structures.  An example of a non-timeless structure is the Tower Bridge in London. It isn't eternal.

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Any differentiation between parts would involve the input of an external observer who existed in time.
I don't see why an observer is necessary.  Observation is necessary for said differentiation between parts to be known by said observer, but differentiation need not necessarily be known by anything.
 
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How can a set, or sequence, of anything have any meaning if it is not possible to consider individual members independently?
Well, we're observing them in this topic, so the problem is moot.  Yes, for the purpose of this topic, we are observing various things and deriving meaning from them.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 07/10/2019 15:07:46
Quote from: Halc
So your statement means "The set of integers might be “eternal” by definition 1, but it has relevance only in terms of the reality in which we perceive ourselves to be existing."
I must disagree with that.  A different reality would also find integers relevant, although not necessarily all realities.


Perhaps it would have been better if I had said something like: “That in which we, or any other entity we might choose to imagine, could conceivably visualise ourselves as existing”.  However, I am inclined to think that any such hypothetical realities that found integers relevant, would be realities that experienced time.

Recall that “timelessness” is integral to Def. 2 of eternity.

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As I said, I have an inherent bias against anthropocentric views.

There is nothing essentially anthropocentric about our “finite reality”, it existed before any anthropoids of which we have knowledge appeared.  The denizens of a “reality” would be unlikely to pre-date that “reality”, which is one reason why I, too, tend to eschew anthropocentric theories. 

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don't see any mention in either def about a thing itself being finite or not.

That’s because both are definitions of eternity, not of the nature of any possible “inhabitant” of eternity.

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Def 1 talks about time being infinite, but the set of integers is not a temporal structure.  It has no time at all, let alone finite or infinite time.

Which is precisely why I reason that infinity/eternity under Def 1 is a convenient usage that is an approximation, at best, and should not be confused with Def 2.

Several more things to address in that post, but out of time again.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 07/10/2019 20:37:42
I am inclined to think that any such hypothetical realities that found integers relevant, would be realities that experienced time.
I probably agree, but 8 is less than 13 whether or not there is a reality in which the integers are found relevant.  That relation of 'less than' is not a perception-dependent relation.  So this reality where there is an experience of time is irrelevant to the nature of the integers, which are themselves timeless.  I can't prove that integers are not dependent on perception, but to assert otherwise is to assert idealism: reality supervening on perception instead of the other way around.

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As I said, I have an inherent bias against anthropocentric views.
There is nothing essentially anthropocentric about our “finite reality”, it existed before any anthropoids of which we have knowledge appeared.
That, on the other hand, is a realist position.  My problem with a realist position is that it doesn't explain why it's there instead of nothing.  I've been trying to explain how I resolve this problem.

Yes, I agree, but would word it as: Certain things (Earth for instance) were created before and existed in this solar system before there were humans (or any life for that matter) to perceive it.
I would not say 'reality' existed before me because parts of what you'd probably consider reality are in our future, not past, so it isn't all on one side of us like that.
I'm also not a realist, so I don't say things 'exist' at all.  For instance, I say the Earth existed 'in this solar system' above, which makes it a relation instead of an ontological property. The relativist position is most of what solves the something-not-nothing issue.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 07/10/2019 21:48:03
Why is there something rather than nothing is a question asking for a cause. How could there be a cause to the existence of the Universe? How could there be a cause to the intrinsic and fundamental structure of the Universe? How could there be a beginning in the first place? There is no beginning and no cause. Energy is conserved... There is no proof of the contrary. Only when energy will not be conserved in a controlled experiment we could start to discuss about it.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 08/10/2019 23:13:42
Quote from: Bill
Let’s look at two definitions of eternity.

1. Infinite or unending time.

2. A state to which time has no application; timelessness.

At first glance, these appear contradictory, but, “common usage by educated people” demonstrates that both are useful definitions, in different contexts.  Would you agree with that?

Quote from: Halc
Of course.  Didn't say otherwise.  But those are different meanings, and if ambiguous, it should be made clear which is meant in a statement.

In spite of this, we still have examples of using one definition to “explain” factors in the other.

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A timeless structure does not exist within time,


Agreed. (Def. 2)

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but time can still exist within it.

Only by Def. 1.   

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   An example of a non-timeless structure is the Tower Bridge in London. It isn't eternal.

Agreed, but consider that if “a non-timeless structure….isn't eternal”, it follows that an eternal structure is timeless.  A problem with trying to embed a non-timeless structure in a timeless structure is that it conflates the two definitions.

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The chess example and our 'cosmos' are both such examples of timeless temporal structures.

Only if you mix Defs 1 and 2. 
By “our 'cosmos'”, do you mean our Universe? I have aimed for clarity in my usage of these terms, and if you are using “cosmos” sensu Gribbin, then I agree it is timeless, but remain unconvinced that it is “temporal”.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 09/10/2019 01:10:01
Let’s look at two definitions of eternity.

1. Infinite or unending time.

2. A state to which time has no application; timelessness.

At first glance, these appear contradictory, but, “common usage by educated people” demonstrates that both are useful definitions, in different contexts.
...
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A timeless structure does not exist within time,
Agreed. (Def. 2)
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but time can still exist within it.
Only by Def. 1.
Def 1 talks about infinite time. Finite time within a structure is not eternity by def 1. Time as we know it (that which is measured in seconds) seems to be finite in some models, and not others. Some of the examples I gave are definitely finite, and some are not, and some have no time at all.

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An example of a non-timeless structure is the Tower Bridge in London. It isn't eternal.
Agreed, but consider that if “a non-timeless structure….isn't eternal”, it follows that an eternal structure is timeless.
If you are using def 2, yes, where 'timeless' means 'not contained in time' and not 'doesn't contain time'.

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A problem with trying to embed a non-timeless structure in a timeless structure is that it conflates the two definitions.
So what? I can glue my inaccurate time piece to the wall so it runs fast and is also fast to the wall.  Is that offensive that the same word means two different things in relation to the same object?
Perhaps better to converse in a language that forbids multiple meanings to any one word.  The dictionary wouldn't be much larger, but there would be a lot more, shorter entries in it.

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The chess example and our 'cosmos' are both such examples of timeless temporal structures.
Only if you mix Defs 1 and 2.[/quote]Mix is OK.  Both are eternal by def 2.  Only the cosmos may be eternal by def 1.  The chess example is not, so there's no dual usage of a word going on there.  Temporal and eternal mean different things.

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By “our 'cosmos'”, do you mean our Universe?
No. Using your definition. Our universe is likely 'caused' by something more fundamental. Cosmos, by your definition, is not. The structure is larger than our 'universe' which is a word I tend to use to describe our particular bubble of space-time.  I think you limited that definition even further by saying it's all we can observe, but then it's not eternal (1) since we only observe finite time.

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I have aimed for clarity in my usage of these terms, and if you are using “cosmos” sensu Gribbin, then I agree it is timeless, but remain unconvinced that it is “temporal”.
It contains my running fast clock, so that makes it temporal.  Does that word mean something different to you?  Dictionary says 'relating to time'.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 09/10/2019 13:57:47
Quote from: CPT Archangel
Why is there something rather than nothing is a question asking for a cause.

This is why I would rather ask; “How could there be…” rather than: “Why is there…”

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How could there be a cause to the existence of the Universe? How could there be a cause to the intrinsic and fundamental structure of the Universe?

It depends on your definition of “Universe”.  Using Gribbin’s distinction; I would say your questions, if applied to “cosmos”, would invite the answer: “there couldn’t be a cause”.  Applied to “Universe”: there probably could be a cause, but I have no idea what it might be. 

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There is no beginning and no cause.

On a cosmic scale I agree. 

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Energy is conserved... There is no proof of the contrary. Only when energy will not be conserved in a controlled experiment we could start to discuss about it.

Point taken; but I suspect that conservation of energy in an expanding universe might raise complications that are best avoided at this stage.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 09/10/2019 16:56:11
Quote from: Halc
Time as we know it (that which is measured in seconds) seems to be finite in some models, and not others.

The point that seems easily to be overlooked/ignored is that time cannot be infinite in any model that asserts that infinity is not a number. Def. 1 sidesteps the “not a number” issue, for convenience.  I have no quarrel with this.

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If you are using def 2, yes, where 'timeless' means 'not contained in time' and not 'doesn't contain time'.

(2. A state to which time has no application; timelessness.)  If time is not applicable under Def. 2; then 'timeless' means 'not contained in time' and  'doesn't contain time'.

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So what? I can glue my inaccurate time piece to the wall so it runs fast and is also fast to the wall.  Is that offensive that the same word means two different things in relation to the same object?
Of course it’s not; nor is that example, in any way, helpful in the consideration of any differences there might be between “infinity” by Defs 1 and 2.

I would like to address the final point in #127 separately, partly because I think it is too important to become lost among other points, and also because I need to give it some thought – possibly, pick some stones out of the path, first.  :)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 09/10/2019 18:10:20
The Universe means everything. If I'm correct, that's the usual meaning of Universe with a capital 'U'. The Big Bang is not the beginning, it is just a phase.

Gravitational waves were postulated to conserved energy. And there we have them...

If you start with an infinite Universe, you won't find any satisfying solution because infinity cannot be rationalized. Yet, we have a constant speed of light in the vacuum, we have other constants and discreet particles. Let's start with a finite Universe, then we may add things to it only when no other solution is reasonable. In a finite and quantized Universe, there is a maximum to entropy...

Let's test a Big Bounce hypothesis where the Big Bang is just a phase transition.

Just before the Big Bang, all matter is condensed in an object having the lowest possible entropy. This could be a Schwarzchild black hole but it includes all space and time (no external space). This implies a prior Big Crunch which has condensed all matter in the previous cycle. This means there was an excess of attraction vs repulsion.

When the Universe reaches the bottom (the lowest entropy), the attractive force (whatever produces this force) passes by a symmetrical point where it becomes null and then this produces an excess of the repulsive force for a brief moment, something like a Planck time. Gravity disappears when the energy budget is 50-50, repulsion-attraction. But in fact, it never gets to this budget because it is a symmetrical point where attraction just disappears. It implies that there are asymmetries left to account for the structure. These asymmetries may be fundamental or related to a multiverse.

A finite Universe implies intrinsic asymmetries. Only an infinite Universe may have a complete symmetry. If you want a cause to our existence, it is the fact that there are irreducible physical asymmetries. The annihilation of an electron-positron pair doesn't result in nothing but two photons. This means there is no complete symmetry between them, though there are symmetries to be filled with the rest of the Universe.

Returning to the Big Bang, this results in a delay between repulsion and attraction.  The phase of repulsion is in advance of the attractive phase. This is dark energy.  Now the Universe has a much greater asymmetry in the form of a delay in the phase of the waves. Repulsion results in an increase in the degrees of freedom and the entropy. Attraction results in a decrease in the degrees of freedom. All forces should be mediated by particles. The known candidate for this effect is the photon which produces a delay of gravity in its direction of motion. Gravity moves at the speed of light. This adds to the original delay, though it is small, it means Dark Energy increases. But, as the Universe is finite, it will reach a maximum entropy and go through another phase transition when a symmetry of the repulsion force will be filled in. Dark matter has an important role to account for the ratio of gravitational mass vs repulsive mass. It could potentially have only an attractive component.

GR does not include the phase transitions or the Big Bang...
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 09/10/2019 18:27:18
Thanks CPT Archangel. That’s a great explanation for the evolution of the Universe.  There are so many things in it that merit attention, it probably needs a thread of its own.  I look forward to returning to it. 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 09/10/2019 23:53:24
Quote from: Halc
Time as we know it (that which is measured in seconds) seems to be finite in some models, and not others.
The point that seems easily to be overlooked/ignored is that time cannot be infinite in any model that asserts that infinity is not a number.
I know of no models that defy the rules of mathematics and assert any such thing.

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If you are using def 2, yes, where 'timeless' means 'not contained in time' and not 'doesn't contain time'.

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(2. A state to which time has no application; timelessness.)  If time is not applicable under Def. 2; then 'timeless' means 'not contained in time' and  'doesn't contain time'.
Def 2 is a 2nd definition of eternal (or eternity), and that does not preclude things that contain time, as our universe obviously does.  I consider it to be eternal but not timeless.

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So what? I can glue my inaccurate time piece to the wall so it runs fast and is also fast to the wall.  Is that offensive that the same word means two different things in relation to the same object?
Of course it’s not; nor is that example, in any way, helpful in the consideration of any differences there might be between “infinity” by Defs 1 and 2.
I wasn't commenting on the differences.  I was responding to your comment about conflating the two definitions of eternity.  'Infinity' is not mentioned in Def 2.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 11/10/2019 16:20:27
Quote from: Halc
I know of no models that defy the rules of mathematics and assert any such thing.

Nor I, but we still find, in the same post, things like: “Eternity is not a length of time.” and “Just think of it as infinite time”  While this can be explained away, that does require changing definitions. 

We seem to have agreed that one-word-one-definition is neither attainable, nor desirable, but some agreement about definition, in any specific context, is essential. 

I think we have agreed that infinity is not a number, and eternity not a length of time.  If so, perhaps we should have a go at defining a sequence. 

My suggestion for a starting point is: “A sequence is a statement of a particular order in which related entities follow one other”.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 11/10/2019 17:17:52
That presumes a relationship.

"He put his hat on, walked out of the door, and was shot by a sniper."  Obvious sequence (it could not have happened in any other order) but no essential relationship between the events. Interestingly, it could be the start of a novel in which the detective looks for a connection, but this sort of thing happens in real life with none.

So a sequence is a temporal or spatial order. Not to be confused with a series, where there is a logical connection such that the next member is predictable from those we already know.

"He put on his body armour, opened the hatch, and was met by a hail of fire from the enemy." Implicit context turns a sequence into a series!
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 11/10/2019 19:09:07
Quote from: Halc
I know of no models that defy the rules of mathematics and assert any such thing.

Nor I, but we still find, in the same post, things like: “Eternity is not a length of time.” and “Just think of it as infinite time”  While this can be explained away, that does require changing definitions. 

I think we have agreed that infinity is not a number, and eternity not a length of time.  If so, perhaps we should have a go at defining a sequence.
I would have said that by def 1, it is a length of time, but not one that can be represented by a number.  It is an unbounded length of time.  The difference between how we see it seems unimportant to what is being asked in this thread.

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My suggestion for a starting point is: “A sequence is a statement of a particular order in which related entities follow one other”.
That 'statement' is pretty much the same thing as a reference frame or a coordinate system, either of which accomplishes the same thing.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 11/10/2019 20:08:20
Alan,

Your definition of a sequence is good, but I don't think you are right by saying that the sequence "He put his hat on, walked out of the door, and was shot by a sniper." is non causal. Your brain separates artificially the causal relations after the fact from your own perspective and knowledge. Unless you believe in freewill, the universe determines the sequence and everything is causal. For example, if he didn't put his hat on, maybe the sniper wouldn't have recognized him and never killed him. Even though the hat may not have played a crucial role, it is still a part of the causality chain and the Universe produces only one outcome. But some events are more important than others. Everything in your past light cone, including your own body, determines what you're doing.  Why the sniper shot him? why the sniper is a sniper? What happened when he was young to become a sniper? How were his parents, his family, his environment and his parents parents and so on? In the end, you can safely conclude that the Big Bang is the origin... I prefer to say it is the way the Universe is. It is also true in the Many-Worlds interpretation, even though I think it is wrong.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 12/10/2019 11:46:41
Quote from: Bill
I think we have agreed that infinity is not a number, and eternity not a length of time.

Quote from: Halc
I would have said that by def 1, it is a length of time, but not one that can be represented by a number.

Quote from: Lewis Carroll
When he cried "Steer to starboard, but keep her head larboard!"
   What on earth was the helmsman to do?”


A length of time that cannot be represented by a number. Material for the imagination!  The only length of time I can think of that cannot be represented by a number is “infinite” time; which is a contradiction in terms.

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The difference between how we see it seems unimportant to what is being asked in this thread.

Possibly because the connection is still to be made.

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That 'statement' is pretty much the same thing as a reference frame or a coordinate system, either of which accomplishes the same thing.

A great response, if you want to keep the door open for agreeing, or disagreeing with the proposed definition, later.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 12/10/2019 14:28:23
Quote from: Alan
"He put his hat on, walked out of the door, and was shot by a sniper."  Obvious sequence (it could not have happened in any other order)

What about: "He, walked out of the door, put his hat on and was shot by a sniper."?  If the shot is not fatal, there are other possibilities as well; or am I missing something?

Nit-pickers of the world unite,
The details are exciting;
We could argue through the night,
And reach the morning fighting.

Good distinction between “series” and “sequence”; thanks Alan.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 12/10/2019 17:05:14
Arkangel: the sequence hat/door/shot is not implicitly or explicitly causal. That's the problem of forensic science - we an establish a sequence of events, but the law demands to know whether he was shot because he was wearing an enemy hat (an act of war) or any hat (an act of insanity) or the hat was irrelevant to the shooting (terrorism).  He might not have been shot if he hadn't opened the door, but if the shooter really wanted to kill him, he would have kicked the door in or fired through the window anyway. 

There's a very neat mathematical introduction to forensics. What is 2 + 2? What is 3 + 1? What is 6 - 2? That's everyday maths. What is 4? That's forensic maths.

Bill: I never said the shot was fatal! Beware of "obvious" implications. It makes no difference to the sequence of events so far, only to subsequent events, of which we currently know nothing. Here's what actually happened:

He put on his hat, walked out of the door, and was shot by a sniper. The shot grazed his left arm but, after the commercial break, 007 replied, firing his automatic from the hip, and blew the sniper's head off.....Unoriginal screenplay by Alan Calverd.....
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 12/10/2019 18:24:24
If you search for who did it, you are right. But in terms of cause, no. Our society is totally wrong on how we blame people, simply because only the Universe is guilty. It doesn't mean we should do nothing to stop criminals, it just means we should change our way of thinking and take care of everybody's environment. We are treating symptoms not the disease...

There are levels of physical causation but it is all emergent from particles interactions. Forensic investigation looks from the top and doesn't go very deep.

You are totally right from the standard emergent point of view of people. But physics shows it is wrong...
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 12/10/2019 21:17:50
Quote from: Alan
Bill: I never said the shot was fatal!

What we say (or write) passes through the filter of our background, learning and understanding, giving rise to our interpretation.  The person who hears what we say, passes it through a similar filter; thus, producing an interpretation that may well be very different from ours.  The surprising thing is that we ever fully understand one another.  Or do we?  Does anyone really hear what we say?

Let’s avoid an “I didn’t say…”, “I didn’t say you said….” Situation, and move on. :)

What I was looking for (initially) when introducing a definition of a sequence to this thread was to investigate the (possibly) numeric nature of a sequence, and consider the implications of a (possibly) infinite sequence.  Eventually, I would hope to link that to the OP.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: HelpMe929 on 14/10/2019 06:56:21
Deciding how the universe came into existence is one question.

Deciding if the universe exists at all is another one. Existence is an effect. What is the cause? There is nothing concrete that I can pick out from 'popular science' (as opposed to hard science from the scientists' workbench) that points to anything you can put your finger on as saying 'this is the building block for everything'.

There seems to be no current detectable limit to the external universe, and no current detectable limit to the inner universe of microphysics. Like a mandlebrot pattern, the physical universe seems to have unlimited granularity. I like to think that the search for physical unification is like looking for the simple underlying formula for mandelbrotian chaos .

I like the quote from 'Hitch-hiker's guide to the Galaxy'

"There is a scientific theory which states that the moment we understand the universe around us it will instantly be replaced by a more complex one... There's is another theory which states that this has already happened."
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 14/10/2019 07:52:54
What we say (or write) passes through the filter of our background, learning and understanding, giving rise to our interpretation.  The person who hears what we say, passes it through a similar filter; thus, producing an interpretation that may well be very different from ours.  The surprising thing is that we ever fully understand one another.  Or do we?  Does anyone really hear what we say?
You have identified the essence of comedy and lightweight drama: set up a scene that elicits the audience's expectations of "normal", then flip to the plausible but unexpected. It is also the essence of a lot of science: the anomalous observation that leads to understanding, is only anomalous in preconception, not nature.

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What I was looking for (initially) when introducing a definition of a sequence to this thread was to investigate the (possibly) numeric nature of a sequence, and consider the implications of a (possibly) infinite sequence.  Eventually, I would hope to link that to the OP.
Back to the subject! We can attach numbers to the items in a sequence but they can be misleading. We can see an expanding universe and what appears to be a residual microwave background, so it is tempting to presume an origin as t → 0 and an asymptotic thermal death as t →∞, but we know that we can only observe within the Schwarzchild limit so we should not be surprised if we are surprised and the observable universe decides one day to contract - the laws of physics are descriptive, not prescriptive.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 14/10/2019 20:46:14
Alan, I have no problem/argument with any of that.  What does give me pause for thought is the concept of an infinite sequence.  As I have said before, I accept this without quibble, as long as it is defined and used in a finite, mathematical context. 

Hilbert’s Hotel is a good example.  It’s a clever bit of manipulation which “solves” a problem, in a temporal context.  It doesn’t actually solve the problem of finding a room for an extra guest, when an infinite number of rooms is already filled with an infinite number of guests.  All it means is that an ever-changing succession of individuals is without a room, for all eternity. 

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So a sequence is a temporal or spatial order

Fine; but it is an order of “things” – physical things, ideas, mental images etc – the individual entity is essential to the whole.  A sequence of “nothing” might be acceptable in the work of to Lear or Carroll, but, otherwise, is difficult to take seriously.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 14/10/2019 20:59:45
Quote from: Help Me
There seems to be no current detectable limit to the external universe, and no current detectable limit to the inner universe of microphysics.

I think the key word there is “detectable”, but does the significance of “detectable” change if we are considering finite or infinite scenarios, or if we use either Def 1 or Def 2 of infinity/eternity?   
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 14/10/2019 23:09:37
A sequence of “nothing” might be acceptable in the work of to Lear or Carroll, but, otherwise, is difficult to take seriously.
Carroll was a serious mathematician. A new diary is a sequence of nothing, and you can have as many as you like, so in principle it is a sample of an infinite sequence of nothings.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 15/10/2019 13:14:27
“You cannot be serious!!” (with a US accent, of course)

You have a diary without pages, dates, etc? 
We are back to the many definitions of “nothing”, and comments like “there’s nothing in this room”, when you mean “what I’m looking for is not in this room”. 

I don’t like the use of “absolutely nothing” any more than I like “absolutely perfect” or other tautologies; but if it avoids mixing definitions, I’ll go with it.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: RobC on 15/10/2019 14:01:19
Relevant to this thread?

"Truth is ever to be found in simplicity, and not in the multiplicity and confusion of things".
-- Sir Isaac Newton
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 15/10/2019 14:20:29
The diary has dated spaces but no content. The dates (an infinite series of integers) aren't content and have no significance in the absence of content, but they will serve to record and predict the sequence of whatever content I insert. But since the content will consist of stuff like "dog to vet" and "pay VAT", it will never be a series: the events have no necessary connection and cannot be predicted from the study of prior events.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 15/10/2019 18:40:59
Quote from: Rob
Relevant to this thread?

"Truth is ever to be found in simplicity, and not in the multiplicity and confusion of things".
-- Sir Isaac Newton

Absolutely relevant, but how would experts manage always to be right if they were not experts in multiplying confusion? :)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 15/10/2019 18:43:10
Alan, I agree with what you say, as long as we are defining “something” as what you consider to be significant in the context.  Nothing personal, but unless specified and agreed upon, I would be inclined to work with a more generalised definition of both “something” and “nothing”. 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 15/10/2019 19:03:01
https://www.livescience.com/28132-what-is-nothing-physicists-debate.html

What hope is there for mere mortals?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 16/10/2019 08:18:51
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"It has a topology, it has a shape, it's a physical object," philosopher Jim Holt said
Yet another instance of pretentious drivel from a philosopher. Why does anyone bother to invite such people to speak? If you define "nothing"  as an absence of physical objects, it cannot be one. And there is no other meaningful definition.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 17/10/2019 17:18:12
Krauss holds out the promise of some deep insight into the nature of “nothing" with: “.. there is a deeper kind of nothing”,  Wow! Tell us about it. Then, after a very general description, he says:  "That to me is as close to nothing as you can get".  Is he saying we can never “attain” nothing – it is out of our reach – it is nothing?  Would that have been too prosaic for so illustrious an assembly?

Alan, you should have been there.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 17/10/2019 17:22:55
Nothing: the value of philosophy.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 17/10/2019 18:26:44
Should Krauss have been a philosopher? In his book, “A Universe From Nothing” he looks at the difference between something and nothing, and somehow ends up with God, who, he insists, doesn’t exist.  God = nothing. A profound assertion, but is it science? 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 17/10/2019 18:36:37
Assertion never equals science. Our business is all about doubt.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bogie_smiles on 18/10/2019 02:43:34
Assertion never equals science. Our business is all about doubt.
I don't doubt you, but can you explain?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 18/10/2019 09:51:27
Science is the recursive process of observe, hypothesise, test. If you didn't doubt, you wouldn't test, so you wouldn't  be doing science. "Assert" does not appear anywhere in the process, though you might take well-established test results as temporary "givens" to speed things up.

Politics, philosophy and economics are all about assertion. It doesn't matter because no politician, philosopher or economist ever admits to being wrong, just misunderstood. Hence the popularity of PPE degrees among politicians (not to be confused with  Personal Protective Equipment worn by people with proper jobs): unlike History (where dates matter) there are no wrong answers in a PPE exam.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 19/10/2019 11:11:19
Quote
unlike History (where dates matter) there are no wrong answers in a PPE exam.

Now I know how I passed A Level Sociology, with the best mark at that Centre, in spite of making up my answers as I went along.  I even made up quotes from obscure non-existent American studies. :)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 19/10/2019 11:30:43
I wonder if this thread is meandering towards the sort of inconclusive “death” that often seems to befall long, drifting threads.  If that is the case, I would like to acknowledge the fact that there is a lot of thought-provoking material in it; and to thank those who have been patient with my apparent intransigence; especially Halc and Alan, who have born the brunt.

The thread deserves a summary.  I don’t have time for that, but will try to make some sort of link between the current position and the OP.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 19/10/2019 17:02:52
I even made up quotes from obscure non-existent American studies.
Congratulations!

If you don't already know about it, https://en.wikipedia.org/wiki/Sokal_affair is a good summary of a famous spoof. It also invokes the concept of "postmodern philosophy". Now if "modern" means "now", "postmodern" must mean "tomorrow"/. Isn't this what us humans call science fiction?

I think we are making progress! The expansion of the universe is due to philosophers filling all the empty spaces with bullshit.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 20/10/2019 15:21:39
This is not an attempted summary, but as we seem to have drifted into a discussion of “nothing” it might be worth seeing how that links back to the OP.

Since “nothing” is just that - nothing; it cannot be said to exist in any way or form. 
If “nothing” cannot exist, it follows that there must always have been “something”.
If we consider our Universe to be everything that exists; the Big Bang cannot have been the beginning of the Universe. 
If our universe started with the Big Bang, it cannot be all there is.  Something must have preceded it.
A common way round this is to multiply the definitions of the universe.  This can work, but tends to lead to misunderstanding. 
Using Gribbin’s distinction between cosmos and Universe seems unpopular, but is one way of avoiding “crossed wires”.
Whatever terminology one uses, there must always have been something, or there would be no Universe now.

Does this answer the OP’s question?  Only Akabiz can answer that, but where is Akabiz?  :)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 20/10/2019 17:48:11
Since “nothing” is just that - nothing; it cannot be said to exist in any way or form. 
If “nothing” cannot exist, it follows that there must always have been “something”.
This seems like a serious set of logical errors.
If a bucket contains nothing, then nothing exists in the bucket. Nothing existing means 'lack of something being in there', not 'there's something there, and that thing is a nothing'.
It is the equivalent of a set of things that 'exist' being an empty set.  There is nothing in logic that says that there is some sort of contradiction in that set being empty.  Thus it does not follow that 1) the set must be nonempty and 2) that the set suddenly has temporal properties with members that change over time.  You've changed the set from 'that which exists' to the set of 'that which currently exists', which is an invalid transformation.


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If we consider our Universe to be everything that exists;
Circular.  Then you cannot say the universe exists.  The universe, if it exists, is a member of [everything that exists].  That's a better statement.  'Universe' is a member, and 'cosmos' (by your earlier definition) is either the set or the entire contents of the set, which may or may not be empty.

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If our universe started with the Big Bang, it cannot be all there is.  Something must have preceded it.
The universe appears to be an object within a larger structure, yes.  Hence it was likely 'caused' in a manner of speaking, yes.  I agree with this, but it does not follow that time (the time in which the universe was created, not the time contained by it) is either finite or infinite in either direction.  I don't think the distinction matters, because even with infinite past, the question of why the [set of things that exist] is non-empty hasn't been resolved.  Playing games with finite/infinite time is merely in pursuit of why something might be a member of the set of things which currently exist, and I don't care about that since it presumes time exists and thus begs an answer to the former question.

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Does this answer the OP’s question?  Only Akabiz can answer that, but where is Akabiz?  :)
Akabiz is gone, a 1-post wonder.  He was asking a different question which is why I didn't bother answering.  He just pointed out evidence of objects with an apparent age older than the time since the BB, which is rightly a contradiction that needs resolution.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 20/10/2019 20:00:50
Quote from: Bill
Since “nothing” is just that - nothing; it cannot be said to exist in any way or form.
If “nothing” cannot exist, it follows that there must always have been “something”.

Quote from: Halc
This seems like a serious set of logical errors.
If a bucket contains nothing, then nothing exists in the bucket.

We are back to juggling with the meaning of nothing.  Isn’t a bucket something?

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Nothing existing means 'lack of something being in there', not 'there's something there, and that thing is a nothing'.

How do you equate that with “If a bucket contains nothing, then nothing exists in the bucket”?

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It is the equivalent of a set of things that 'exist' being an empty set.  There is nothing in logic that says that there is some sort of contradiction in that set being empty.  Thus it does not follow that 1) the set must be nonempty and 2) that the set suddenly has temporal properties with members that change over time.  You've changed the set from 'that which exists' to the set of 'that which currently exists', which is an invalid transformation.

I’m talking about “nothing”, you seem to be talking about sets.  Are sets “nothing” or are we talking about completely different things?

Quote from: Bill
If we consider our Universe to be everything that exists;

Perhaps, if you put that quote back in context, your response might be different.

Quote from: Bill
If our universe started with the Big Bang, it cannot be all there is.  Something must have preceded it.

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I agree with this, but it does not follow that time (the time in which the universe was created, not the time contained by it) is either finite or infinite in either direction.

Where did I mention finite or infinite time?

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I don't think the distinction matters, because even with infinite past, the question of why the [set of things that exist] is non-empty hasn't been resolved.

Could it be that we need to distinguish between “a set containing nothing”, which may or may not exist, and (absolutely) nothing, which would not involve sets of anything?

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Playing games with finite/infinite time is merely in pursuit of why something might be a member of the set of things which currently exist, and I don't care about that since it presumes time exists and thus begs an answer to the former question.

I’m willing to accept that I may have said something unintentional, but I have serious problems with the concept of “infinite time”, so I need to know what I might have said to give the impression I was “playing games” with it.

Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 21/10/2019 00:29:05
We are back to juggling with the meaning of nothing.  Isn’t a bucket something?
Yes, but I didn't say the bucket was nothing, just that there was nothing in it, or rather (by my definition below), it doesn't contain anything.  Importantly, I didn't assert the bucket existed or didn't exist.  The words have no meaning to me either way, so I didn't say them.
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Nothing existing means 'lack of something being in there', not 'there's something there, and that thing is a nothing'.
How do you equate that with “If a bucket contains nothing, then nothing exists in the bucket”?
The bucket lacks any contents, so a list of what exists in the bucket is empty.

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I’m talking about “nothing”, you seem to be talking about sets.
I'm talking about 'nothing' equating to an empty set.  You seem to hold an assumption that certain things have the property of 'exists', so I'm formally expressing that concept in set notation saying that these things are members of a set of all things that have this property.  That makes it a relation, allowing us to speak the same language, since I only see existence as a relation, not a property.

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Are sets “nothing” or are we talking about completely different things?
No.  For instance, in the set of integers, there is nothing between 5 and 6. I suppose that could be a set of all integers between 5 and 6 if you want to word it that way.

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Quote from: Bill
If we consider our Universe to be everything that exists;
Perhaps, if you put that quote back in context, your response might be different.
OK.  You said "If we consider our Universe to be everything that exists; the Big Bang cannot have been the beginning of the Universe."
I don't think that follows. Suppose the universe is everything that exists and it begins at the big bang.  It is bounded in the temporal direction at that one moment.  What's inconsistent about that?  I don't think it's the case, but I cannot prove it's not the case, but your statement above indicates that it not being the case is impossible or contradictory or something.  For that matter, I cannot prove the universe didn't begin last Tuesday. For the same reasons one might argue the latter point, your statement above doesn't seem to follow.

Quote from: Bill
If our universe started with the Big Bang, it cannot be all there is.  Something must have preceded it.

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Where did I mention finite or infinite time?
In many posts in this thread's history, recently in discussion of definition of eternity.

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Could it be that we need to distinguish between “a set containing nothing”, which may or may not exist, and (absolutely) nothing, which would not involve sets of anything?
Well, I didn't say the {set of all things that exist} contains itself.  I find 'a set not containing anything' more clearly worded than 'a set containing nothing', but they mean the same thing.
Absolute nothing just means the set of all things that exist is empty, and definitely doesn't include itself. How would you prove that that isn't the case? An object with the property of existence would need to behave empirically different than the same object without that property, else there's no empirical distinction. I argue the lack of that distinction. Existence is thus not a scientific property, but it is a scientific relation: I can distinguish an empty bucket from one in which an apple exists. The apple has a relation of 'existing in' with the bucket.

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I have serious problems with the concept of “infinite time”, so I need to know what I might have said to give the impression I was “playing games” with it.
As I was trying to say, my argument above does not hinge on time, finite or not.  I consider the discussion a diversion, which is part of why stopped posting while I thought the discussion was on an irrelevant track.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 21/10/2019 01:07:34
Nothing is not something, therefore it does not exist. In physics, space is not nothing but rather something. Space must be included in a good cosmological model. Physicists using the word 'nothing' to mean 'something' are fools. Usually, they have made a mistake and they don't want to admit it. Changing the definition to prove your point is demagoguery. It is the same for people who admit there is no freewill but add their own definition of it to promote their point of view. From a scientific point of view, they are wrong from the beginning.

Personally, I think you need more than space to form a universe. The Universe cannot come from nothing. There is nothing in experimental physics showing that the contrary is possible. It would imply magic...

Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 21/10/2019 12:10:37
Quote from: Bill
Are sets “nothing”

Quote from: Halc
No.

So, in talking about sets, whether they contain anything, or not, you are not talking about nothing.

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  Suppose the universe is everything that exists and it begins at the big bang.

From nothing?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 21/10/2019 12:16:49
Alan sums it up:
 
Quote from: Alan
If you define "nothing"  as an absence of physical objects, it cannot be one. And there is no other meaningful definition.

Archangel put it equally succinctly:
 
Quote from: Archangel
  The Universe cannot come from nothing. There is nothing in experimental physics showing that the contrary is possible. It would imply magic...

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Changing the definition to prove your point is demagoguery.

Possibly, enough said. 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 21/10/2019 12:43:44
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Suppose the universe is everything that exists and it begins at the big bang.
From nothing?
If it is 'from' a nothing, then 'nothing' is something not part of the universe, which contradicts the premise that the universe is everything.  So no, not 'from nothing', but also also no, I'm not defining the universe as everything that exists.

Alan sums it up:
 
Quote from: Alan
If you define "nothing"  as an absence of physical objects, it cannot be one. And there is no other meaningful definition.
OK, but the word loses much meaning given such a narrow definition. The set of integers contains nothing, because it lacks physical objects.  How long before it's my turn?  Nothing, because there's perhaps an hour, but that's not a physical object.

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Archangel put it equally succinctly:
 
Quote from: Archangel
  The Universe cannot come from nothing. There is nothing in experimental physics showing that the contrary is possible. It would imply magic...
I agree that the universe did not come from nothing. Particles in physics do appear without cause, so I cannot agree with that part.  Hawking radiation is such an example.

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Changing the definition to prove your point is demagoguery.
And assuming the answers to prove your point is begging.

My approach has been to use mathematics to analyse the problem, so that it can be studied more formally with known terms.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 21/10/2019 18:58:47
Halc, I was not talking about you but physicists who debated about a universe from nothing.  This is probably where you got the idea.

Particles do not appear without a cause. This is an interpretation, not a fact. Look for the 'measurement problem' in QM. We know that the measurement must influence the outcome of a measurement but QM is blind on this subject. This leads to an easy explanation for randomness: you need a theoretical mechanism for the measurement process and you need the wave function of a sufficient causal part of the universe to collapse the randomness. For example, if you take only two particles in your experiment, you minimize your knowledge about the particles because you neglect all other relations of the ensemble. It is like sending a rocket to Mars while neglecting the influence of the Moon, the Sun and all the rest of the Universe. For the measurement problem, this leads to mixed states with no pure states of entanglement. What it means is the measurement of a single particle is maximally influenced by the measurement and what is measured is a mixture of the entanglement of the particle with the detector and with the rest of the Universe. This is how randomness appears in experiments at a particle scale and why we can predict with high confidence the trajectory of a space probe...

You must take account of all important causal relations to have a power of prediction.

Here, Universe with a capital 'U' means everything.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 21/10/2019 19:33:26
Science is based on reality. A scientific who denies reality is like a marathon runner who shoot himself in the foot at the start of the race...
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 22/10/2019 00:45:05
Particles do not appear without a cause. This is an interpretation, not a fact.
Just so.  Such interpretations support actions now causing effects in the past, and I find that more offensive than events without cause, so I personally choose different interpretations, but as you say, not fact.
So being interpretational, it is not invalid to posit something from nothing, since interpretations that allow it are not invalid.  Again, I'm not personally suggesting the universe came from nothing.

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Look for the 'measurement problem' in QM. We know that the measurement must influence the outcome of a measurement but QM is blind on this subject. This leads to an easy explanation for randomness: you need a theoretical mechanism for the measurement process and you need the wave function of a sufficient causal part of the universe to collapse the randomness.
Maybe you need these things.  There are interpretations with randomness and others without. There are ones with collapse and other without.  I suppose one must select an interpretation before making descriptions based on the interpretation, and then the descriptions are only relevant to the selected interpretation.  That's what I'm trying to do.  Pick an interpretation that solves the whole problem under discussion.

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Here, Universe with a capital 'U' means everything.
I still find the term 'everything' to be loosely defined.  Not sure what somebody else might mean by that. It has little meaning at all to me.

Science is based on reality. A scientific who denies reality is like a marathon runner who shoot himself in the foot at the start of the race...
To me, 'reality' is that which has been measured by something, making it real to that something. I doubt you'd word it that way, so 'reality' is a term subject to interpretation.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 22/10/2019 01:15:45
I was not trying to argue with you, Halc, but I was rather trying to point the flaws in the point of view of what is usually being considered as mainstream. If you ask theoretical physicists, most of them will tell you that there is no mainstream in theoretical physics.

Essentially, what I say is Einstein built his theory by following Mach's principle. It is extraordinary successful. Why not use Mach's principle to unify QM and GR to get a Quantum theory which includes gravity? With my explanations, this is quite logical and resounding. Isn't it?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 22/10/2019 01:26:00
Moreover, there is always holes in any successful theory. I say, rather than trying to fill the holes with everything we could imagine, we should start with the minimum necessary and then add on things from a minimalist perspective. If I remember  correctly, the theoretical estimation of the vacuum energy is 120 orders of magnitude higher than what is being observed at cosmological scale... 1 to the power 120! This is why it is impossible to produce black holes at the LHC but according to some theories, it should be possible.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 22/10/2019 01:41:29
I was not trying to argue with you, Halc, but I was rather trying to point the flaws in the point of view of what is usually being considered as mainstream. If you ask theoretical physicists, most of them will tell you that there is no mainstream in theoretical physics.
I was going to ask what that mainstream view was, since I doubt that I hold it.  There are many subjects, some scientific, and many philosophical.  QM interpretation is one of them, and there seems to be no mainstream view in physics since the interpretations are not science.
There are also views on time, identity, and other subjects, which probably have different mainstream views if you ask the physicists and if you ask the general public.  The latter group tends not to give much thought to what is implied by physics, but then again, most of them are not posting on sites like this one.

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Essentially, what I say is Einstein built his theory by following Mach's principle. It is extraordinary successful. Why not use Mach's principle to unify QM and GR to get a Quantum theory which includes gravity? With my explanations, this is quite logical and resounding. Isn't it?
I'm only mildly familiar with the principle. Unifying the theories cannot be as trivial as mere application of the principle, else it would have been done. No known theory predicts behavior at both levels.

A unified theory would be nice for resolution of the subject matter at hand.  I definitely reach into QM interpretations in making my arguments, and also into some of the implications of relativity theory (which suggests but does not demand an eternal model of the universe)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 22/10/2019 02:35:15
"Unifying the theories cannot be as trivial as mere application of the principle, else it would have been done."

It is not trivial because we are stuck with probabilities in experiments. Bohm's theory is just an example but it does not go far enough. There are many others like causal sets or the Many-Worlds, which is a weirder kind. The thing is when you look at QM from a causal sets point of view, it explains so many things without any contradiction that it is just striking. And this is how GR works. 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 22/10/2019 10:22:44
The set of integers contains nothing
No. The set of integers contains a number that can denote the absence of stuff. Back to school: if I have one apple and you steal one apple from me, how many apples do I have? An integer is not an object.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 22/10/2019 10:27:59
This leads to an easy explanation for randomness: you need a theoretical mechanism for the measurement process and you need the wave function of a sufficient causal part of the universe to collapse the randomness.
I beg to differ. Measurement interference and wave function collapse are mathematical models of what happens, just as 1 - 1 = 0 is a mathematical model of Halc stealing my apple. There are no apples on this screen, and indeterminacy is an essential property of matter, not induced by observation.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 22/10/2019 12:29:20
The set of integers contains nothing
No. The set of integers contains a number that can denote the absence of stuff.
Please don't quote me out of context.
The set of integers contains integers, which is not an example of nothing.

You are using a different definition of 'nothing', which is fine, but then don't interpret my quote using your definition.

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indeterminacy is an essential property of matter, not induced by observation
With this I agree.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 22/10/2019 13:18:01
It is not trivial because we are stuck with probabilities in experiments.
That cannot go away. That's the nature of the world in which we find ourselves, and any theory that does away with it will not describe us. The problem is, quantum field theory does not describe gravity, so the theory falls apart in places where gravity cannot be ignored. Hence we don't have a working model of what goes on at say a black hole event horizon.

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Bohm's theory is just an example but it does not go far enough. There are many others like causal sets or the Many-Worlds, which is a weirder kind.
Bohm's interpretation is full blown acceptance of counterfactual definiteness: That there is a reality that is definitely in some actual state, and that probability arises simply from not being able to know that state.  It is like the shell game where one shell really does contain the token, but until we look under them, we cannot know which.
MWI is also a realist model that says the token is in superposition of being under all three shells, and by peeking, three worlds branch off with the token being in each. It is not a counterfactual interpretation, since the token is not in fact under a specific shell before they are measured.

Realist interpretations suffer from a problem, which is the (current) subject of this topic. It isn't the original subject, but the OP guy has fled the building. The problem is why this universe is real, instead of a different universe, or more in particular, the lack of one?  None of the realist interpretations address that issue, and for that reason I don't buy into either of the interpretations you've mentioned.  Yes, I was a MWI guy for a while, but that point seemed contradictory to me no matter how I looked at it, so I dropped it.

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The thing is when you look at QM from a causal sets point of view, it explains so many things without any contradiction that it is just striking. And this is how GR works.
Causal sets is an attempt at quantum gravity and isn't really an interpretation of QM until it unifies with it. So I don't know how to look at QM from a causal sets POV since it's a theory of gravity. I don't know how it would interpret the Schrodinger's cat scenario for instance. Do you?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 22/10/2019 20:15:52
Superpositions means the probability of finding the state of a particle is 50% up and 50% down. It does not mean it is in a real superposition. You say for you what is real is what can be measured or detected. You can't detect a superposition. Superposition just means you don't have the necessary prior information. Superpositions have never been measured. You either measure up or down. Here I use the 50-50% up down example for simplicity.

The MWI is special because it tries to include the superposition in parallel worlds, but in the end, it is a causal set in many worlds instead of one. There are big problems in the justifications of the cause of the splitting anyway.

Forget the specific theory called Causal Sets Theory, just think of how GR works as a causal set. The farthest star we could see has an impact on us due to gravity, even though you can neglect it in practice because it is too small. Now take a particle and apply this principle to all other interactions...

There is no proof that randomness is fundamental. If you are a tiny part of a huge causal set, you will be stuck with probabilities in practice without having any fundamental randomness. When you throw a ball in the macroscopic world, you can easily get enough information to predict the trajectory but you can't predict with a 100% certainty the exact trajectory, but you could if you had the information on all the rest of the Universe. Now, if you take only a very small number of particles and you have no prior information on them, your power of prediction becomes minimal. Your uncertainty was small for the ball but it is huge for the particles... QM gives the same thing but we need to describe the causal connections for all interactions! And there is quantization, which cause uncertainty by itself in practice (sudden unpredictable steps needing more prior knowledge).

Unrealistic interpretations are not better, they are worst because they all demand more free parameters. Show me a good explanations on why the Universe is the way it is. By Occam's razor, the best should be the one with less free parameters... It is not realistic because it is not real...
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 22/10/2019 21:31:55
Aharonov and his team have lately demonstrated a dependency of the phase of photons and their positions on interference patterns. Not knowing the phase adds to the uncertainty. Not explained by QM random interpretations.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 22/10/2019 22:17:59
On the measurement problem by Sabine Hossenfelder:

http://backreaction.blogspot.com/

When I speak of the wave function of the Universe, I don't speak of a function giving probabilities but a real function which includes all wave-particles having real trajectories and their intrinsic properties (space-time included). The QM wave-function is not real but represents our expectations due to our limited knowledge. In that sense, I am not a realist. Though QM wave-function includes a part of reality demonstrated by its predictive power which comes from the limited but valid prior knowledge.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 23/10/2019 05:49:45
Superpositions means the probability of finding the state of a particle is 50% up and 50% down.
I'm no QM expert, but are you saying that superposition is confined to spin measurements, and to 50/50 probabilities? Given what you say below, I don't think you mean that, but it sounds like just an epistemological assertion:  I toss a coin and catch it under my hand and don't know if it's heads or not.  That's not superposition, but your description here seems to indicate it being your understanding of it.

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It does not mean it is in a real superposition.
I've never heard of 'real superposition' as distinct from a different sort of superposition. Kindly give an example or a link or something. You've really lost me with all this.

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You say for you what is real is what can be measured or detected.
I said that under my preferred view, what is real to X is what has been measured by X. It has nothing to do with what can be measured.

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You can't detect a superposition.
Interference is one way superposition is detected. A simple lack of knowledge does not explain interference.

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The MWI is special because it tries to include the superposition in parallel worlds, but in the end, it is a causal set in many worlds instead of one.
I don't know your personal understanding of MWI.  There's typically the actual-splitting-worlds interpretation (De Witt) where ontologically distinct worlds result from a measurement, and then there's the relative state formulation (Everett) which is just one thing.  The former has serious problems in my opinion, but the latter has problems as well.

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The farthest star we could see has an impact on us due to gravity, even though you can neglect it in practice because it is too small.
Not negligible since there's so bloody many of those distant stars.  They have more effect on our potential energy than do the nearby objects.

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There is no proof that randomness is fundamental.
Of course not.  Neither Bohm nor Everett have any randomness in their interpretations, but some others do. Einstein had a significant distaste for it, but most of the QM interpretations at his time posited randomness. I'd love to hear his take on some of the more modern ones.

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Now, if you take only a very small number of particles and you have no prior information on them, your power of prediction becomes minimal.
I'd say the particles do not meaningfully exist at all given no prior information on them. I suppose Bohm would say otherwise since he posits a measurement-independent reality.

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Unrealistic interpretations are not better, they are worst because they all demand more free parameters.
One that is free of contradictions seems better than one with them, but with fewer 'free parameters'.  Not sure what you consider these free parameters to be.  What's your QM interpretation of choice?  Causal sets is not a QM interpretation.  Not without unification with QM at least. I like the relational one (Rovelli, 1994) for the reasons I've posted in this thread.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 23/10/2019 12:00:51
Quote from: Halc
I've never heard of 'real superposition' as distinct from a different sort of superposition.

Possibly this does not refer to “'real superposition' as distinct from a different sort of superposition”, but rather to superposition, as distinct from something that might be proposed as an example of superposition, but is not.
You give a good example of this: “I toss a coin and catch it under my hand and don't know if it's heads or not.  That's not superposition”. 

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I'd say the particles do not meaningfully exist at all

A similar interpretational dichotomy could be involved here.  What is the difference between “existence” and “meaningful existence”? 
I would interpret “meaningful existence” as involving some sort of personal judgement of the value/significance of the entity under consideration, which, presumably, exists.  Is that what you meant?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 23/10/2019 12:26:34
Quote from: Halc
Particles in physics do appear without cause, so I cannot agree with that part.  Hawking radiation is such an example.

I’m really puzzled by this.  I thought that Hawking radiation had a well described cause, and that this depended on the “vacuum” not being “nothing”. 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 23/10/2019 13:26:18
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I'd say the particles do not meaningfully exist at all
What is the difference between “existence” and “meaningful existence”?
I get the wording from the concept of the principle of counterfactual definiteness (PCD).
https://en.wikipedia.org/wiki/Counterfactual_definiteness
Quote from: wiki
(CFD) is the ability to speak "meaningfully" of the definiteness of the results of measurements that have not been performed (i.e., the ability to assume the existence of objects, and properties of objects, even when they have not been measured).
...
In such discussions "meaningfully" means the ability to treat these unmeasured results on an equal footing with measured results in statistical calculations.
My bold.  So for instance, Pilot wave theory holds to CFD, and a photon does in fact go through one slit or the other despite our lack of measurement of that.  A planet 50 billion light years away in fact exists despite the fact that we have not in any way measured it.
An interpretation that does not hold to CFD (any local interpretation in fact) cannot meaningfully say these things. There is no measurement-independent state.

So I said the thing you quoted above because CPD-A² talked about taking "a very small number of particles and you have no prior information on them".  That is a contradiction in an interpretation without CFD.  If there are a few particles, that's information on them, even if the information is not known by anybody.  With CFD, there is no problem with particles that have never been measured.

Quote from: Halc
Particles in physics do appear without cause, so I cannot agree with that part.  Hawking radiation is such an example.
I’m really puzzled by this.  I thought that Hawking radiation had a well described cause, and that this depended on the “vacuum” not being “nothing”.
As I said, I'm no expert here, but my understanding is that virtual particle pair production occurs uncaused all over the place, and most times these pairs immediately self-annihilate, but the tidal forces near an event horizon might pull such particles apart from each other before they can do that.  As they are pulled apart, one gains positive energy and the other negative energy.  The positive one thus becomes a real particle instead of a virtual one.  Something like that....
It happens more with small black holes since the tidal forces are greatest with them.

There are plenty other uncaused events like photon splitting, radioactive decay, etc. but those are not exactly 'particles in space appearing uncaused'.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 23/10/2019 16:40:30
I suspected that CFD might be involved, and was interested to see if you differentiated between “speaking "meaningfully" of the definiteness of the results of measurements”, on the one hand, and making assertions about the existence/non-existence of physical objects in a 3+1 (apparent) reality. 

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As I said, I'm no expert here, but my understanding is that virtual particle pair production occurs uncaused all over the place,

Almost certainly, I know less about it than you do, but my understanding is that pair-production requires that the vacuum be “something” and that there be an input of energy to act on that “something”. 
Can it be asserted that the presence of that “something”, and the input of energy are without cause?
Do we need an impartial referee, here?  :)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 23/10/2019 17:32:06
I’ve just found a comment by JP, for whose views I have the highest regard. 
In a thread similar to this we were in discussion about the something from nothing idea.  The thread became so convoluted that we switched to PMs to look more closely at whether or not we could say that there could never have been nothing. 
He was adamant that we could not make this claim because, “outside the Universe conditions could exist in which something could come from nothing”. 
I pointed out that “conditions” must surely be something; and although the discussion continued for a while, we never really moved beyond his saying: “The problem with the idea that "nothing can come from nothing" is that to scientifically discuss this, we need to come up with a model, and we can't even describe "absolute nothing" scientifically (or at least I haven't seen a scientifically workable definition)”.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 23/10/2019 19:35:17
I suspected that CFD might be involved, and was interested to see if you differentiated between “speaking "meaningfully" of the definiteness of the results of measurements”, on the one hand, and making assertions about the existence/non-existence of physical objects in a 3+1 (apparent) reality. 
I don't see how the CFD thing is related to interpretation of time.  Most interpretations, with or without CFD, work both models of reality (time as a dimension or not).

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My understanding is that pair-production requires that the vacuum be “something” and that there be an input of energy to act on that “something”. 
No energy is needed for virtual pair production since they have zero mass/energy.  But energy is needed to make the virtual particles real.  That has to come from somewhere.
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Can it be asserted that the presence of that “something”, and the input of energy are without cause?
Energy cannot appear uncaused.  That would violate thermodynamic law.
The big bang seems not to violate this since it seems that the universe has zero total energy/mass.  There's enough negative energy to cancel all the positive energy.

I’ve just found a comment by JP, for whose views I have the highest regard. 
In a thread similar to this we were in discussion about the something from nothing idea.  The thread became so convoluted that we switched to PMs to look more closely at whether or not we could say that there could never have been nothing.
Well I'm definitely not in the something from nothing camp.  A realist will say there is something, but not necessarily that it came from nothing, and the whole phrase "ever has been nothing" is a self contradiction.

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He was adamant that we could not make this claim because, “outside the Universe conditions could exist in which something could come from nothing”. I pointed out that “conditions” must surely be something
Excellent point.  Especially if it's phrased as 'existing conditions'.

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and although the discussion continued for a while, we never really moved beyond his saying: “The problem with the idea that "nothing can come from nothing" is that to scientifically discuss this, we need to come up with a model, and we can't even describe "absolute nothing" scientifically (or at least I haven't seen a scientifically workable definition)”.
A model about that for which there is no empirical test isn't a very scientific one.  I don't claim to be discussing science in this thread.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 23/10/2019 21:09:29
Superpositions means the probability of finding the state of a particle is 50% up and 50% down.
I'm no QM expert, but are you saying that superposition is confined to spin measurements, and to 50/50 probabilities? Given what you say below, I don't think you mean that, but it sounds like just an epistemological assertion:  I toss a coin and catch it under my hand and don't know if it's heads or not.  That's not superposition, but your description here seems to indicate it being your understanding of it.

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It does not mean it is in a real superposition.
I've never heard of 'real superposition' as distinct from a different sort of superposition. Kindly give an example or a link or something. You've really lost me with all this.

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You say for you what is real is what can be measured or detected.
I said that under my preferred view, what is real to X is what has been measured by X. It has nothing to do with what can be measured.

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You can't detect a superposition.
Interference is one way superposition is detected. A simple lack of knowledge does not explain interference.

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The MWI is special because it tries to include the superposition in parallel worlds, but in the end, it is a causal set in many worlds instead of one.
I don't know your personal understanding of MWI.  There's typically the actual-splitting-worlds interpretation (De Witt) where ontologically distinct worlds result from a measurement, and then there's the relative state formulation (Everett) which is just one thing.  The former has serious problems in my opinion, but the latter has problems as well.

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The farthest star we could see has an impact on us due to gravity, even though you can neglect it in practice because it is too small.
Not negligible since there's so bloody many of those distant stars.  They have more effect on our potential energy than do the nearby objects.

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There is no proof that randomness is fundamental.
Of course not.  Neither Bohm nor Everett have any randomness in their interpretations, but some others do. Einstein had a significant distaste for it, but most of the QM interpretations at his time posited randomness. I'd love to hear his take on some of the more modern ones.

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Now, if you take only a very small number of particles and you have no prior information on them, your power of prediction becomes minimal.
I'd say the particles do not meaningfully exist at all given no prior information on them. I suppose Bohm would say otherwise since he posits a measurement-independent reality.

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Unrealistic interpretations are not better, they are worst because they all demand more free parameters.
One that is free of contradictions seems better than one with them, but with fewer 'free parameters'.  Not sure what you consider these free parameters to be.  What's your QM interpretation of choice?  Causal sets is not a QM interpretation.  Not without unification with QM at least. I like the relational one (Rovelli, 1994) for the reasons I've posted in this thread.

You don't read carefully. I must admit my writing is generally a high condensate. If you want to understand me you have to read all my posts on this discussion and think about it. But maybe you don't have the background or you just have too much faith in your own beliefs.

I wrote 50-50% is used as an example for simplicity.

Most people think the superposition is real before the measurement and then collapses randomly to a specific value when there is a measurement or an interaction with the system.

What we know is, from our prior knowledge on the system, we can use the wave function to predict what are the possible states at a later measurement. The square of the wave function is a probability distribution which gives you the probability of any specific state within a distribution of possibilities. The measurement gives you a specific state as a result of new knowledge.

The long debate is, why this probability distribution (superposition) seems irreducible but the measurement still gives only specific states. Superposition is never observed.

1- The old rational point of view is simple, there is things you don't know that you need to know in order to predict the exact final state.  This point of view splits into two categories but both mean more work to be done:

A- You can get all the necessary knowledge 

B- There is hidden knowledge you cannot obtain because of the structure and the mechanism.

Category A seems to have been eliminated but there are still loop-holes.

2- Randomness is intrinsic to the system. The major problem is the randomness is not random but follows a complex set of rules giving specific distributions and so on. How is it even possible? This is ridiculous. Applying randomness ad nauseam to vacuum up to cosmology and hoping the models are good. What a joke! This makes good sci-fi stories and that's it from the theoretical point of view.


I told you about my interpretation already. Read my last post and think of it within a causal set.



Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 23/10/2019 23:00:20
You don't read carefully. I must admit my writing is generally a high condensate. If you want to understand me you have to read all my posts on this discussion and think about it. But maybe you don't have the background or you just have too much faith in your own beliefs.
What beliefs do you feel I'm pushing? I am trying to convey what I know about the various interpretations, and I may be wrong about some of them. I'm not asserting the correctness of a specific interpretation.

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I wrote 50-50% is used as an example for simplicity.
I figured that out, and said so.

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Most people think the superposition is real before the measurement and then collapses randomly to a specific value.
Superposition is real (part of fundamental QM theory). Collapse is interpretation dependent and not fundamental to the theory.
But I'm talking about what is (metaphysics), and not about what we know (epistemology).  I don't care if we know the state of something or not. I care if it has a state at all, so 1A and 1B below are metaphysically the same but epistemologically different. QM functionality was part of the universe long before there was anything that understood it, so epistemology isn't going to help us discuss an event like the big bang which happened when nothing was around to know anything about it.

A rock can measure a system, but it cannot manipulate a mathematical model to make predictions.  So I don't care about the ability to predict (other than to verify/falsify one model or another), but I care about what happens when a rock measures system X.

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What we know is from our prior knowledge on the system, we can use the wave function to predict what are the possible states at a later measurement. The square of the wave function is a probability distribution which gives you the probability of a specific state within a distribution of possibilities. The measurement gives you a specific state.
Yes, but knowledge of the system and prediction is exactly what I don't care about in this discussion. I care about any interpretation of what the system state actually is, known or not.

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The long debate is, why this probability function (superposition) is irreducible but the measurement is still a specific state.

1- The old rational point of view is simple, there is things you don't know that you need to know in order to predict the exact final state.  This point of view splits into two categories:

A- You can get all the necessary knowledge 

B- There is hidden knowledge you cannot obtain because of the structure and the mechanism.

Category A seems to have been eliminated but there are still loop-holes.

2- Randomness is intrinsic to the system. The major problem is the randomness is not random but follows a complex set of rules giving specific distributions and so on. How is it even possible? This is ridiculous. Applying randomness ad nauseam to vacuum up to cosmology and hoping the models are good. What a joke! This makes good sci-fi stories and that's it from the theoretical point of view.
Somebody has a clear bias against the intrinsic randomness interpretations. Instead of making fun of it, show where it is inconsistent. I mean, I don't buy it either, but all the interpretations are a joke to somebody who has chosen a different one. You seem to attempt this in mentioning Aharonov's findings in a prior post, but falsification by mocking seems fallacious.

OK, so you listed 1) a category where the system is in some actual state, and our problem is just that we cannot completely know that state.
You then listed category 2 which involves dice rolling, just like Einstein detested.  You missed all the non-random local interpretations like De-Witt's MWI which you've mentioned before. That doesn't seem to fit into either of your categories.  It isn't category 1 since even perfect knowledge won't let you predict the simplest experiment, and it isn't category 2 since no randomness is involved.  I think De Witt's vision has some empirical flaws, but my point here is that there are more categories than the two you've listed.

Your post suggests you're a hidden-variable kind of guy, but not necessarily anything by Bohm who asserts the reality of the wave function. Causal sets is an approach to quantum gravity, not a QM interpretation, and I got pretty lost trying to read about it.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 24/10/2019 02:30:37
Many-worlds is 1-B, the hidden variables are the other branches. There are other interpretations like QBism which are difficult to categorize but they are truly metaphysical.

My point is if you start by stipulating that the randomness is intrinsic then this is the end of it. No explanations for how the measurement influence the outcome. See the blog "backreaction". 

I don't think the Causal sets Theory is good. I speak of a general causal set. Logically, from what we have learned before the Schrodinger equation, the Universe is a causal set. There is no limit to the gravitational and EM fields which means each object is always subject to everything else. Now we have QM, which behaves like a causal set if you start with one particle and and then add particles one at a time. QM does not explain everything besides gravity. QCD, QFT... There is no theoretical synthesis of QM as a theory, It is more like an imperfect predictive operator.

The thing is, there is no reason to believe randomness is fundamental. If you don't look, you won't find anything. I've been thinking and reading about this almost everyday for 9 years now. What I have found is mesmerizing, a huge faith in randomness mostly based on weak and incomplete arguments.

I haven't try to falsify anything by mocking, I just expressed my feeling about it. I am ready to bet anything you like on the fact that Quantum Gravity theory will only be achieved within a realistic theory demonstrating that randomness is emergent.

Superposition being real is a belief. It is a mathematical equation... Which does not correspond to what is being observed as a result of a measurement.

I think I've said enough to at least demonstrate that a causal theory with randomness as being emergent is not only possible but probable. Randomness has been adopted, nearly a hundred years ago, more for historical reasons in a fight for prestige than from true scientific reasoning...
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 24/10/2019 07:59:46
If I remember correctly, there are 26 or so necessary irreducible parameters in the current theories of physics as a whole. Twenty six parameters for 3+1 dimensions, this seems to be a very complex system for only four dimensions. Cosmologists will tell you that the Universe should be much simpler. The more parameters above the number of dimensions plus a few others, the less likely it is. To reduce the number of parameters by a huge factor, you need unification of many of them. Randomness is in the way of progress because physics needs reductionism desperately. We must learn about what's under the hood.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 24/10/2019 13:05:38
Quote from: Halc
I don't see how the CFD thing is related to interpretation of time.  Most interpretations, with or without CFD, work both models of reality (time as a dimension or not).

Interesting that you selected time; presumably from the reference to “a 3+1 (apparent) reality”, and ignored the essence of the quote.

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No energy is needed for virtual pair production since they have zero mass/energy.
 

Shouldn’t that be zero net mass/energy?  If so, that’s quite different.  If something has no mass and no energy, in what sense does it exist?

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The big bang seems not to violate this since it seems that the universe has zero total energy/mass.  There's enough negative energy to cancel all the positive energy.

It’s that “total/net” dichotomy again.

“Zero-energy universe. The zero-energy universe hypothesis proposes that the total amount of energy in the universe is exactly zero: its amount of positive energy in the form of matter is exactly canceled out by its negative energy in the form of gravity.”

Unless you say that positive energy = nothing, and negative energy = nothing, the “zero” must refer to net energy, not total energy.  Of course, I could have that wrong, but I do tend towards a pragmatic view.

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Well I'm definitely not in the something from nothing camp.

I think that’s worth a “gold star”.

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….the whole phrase "ever has been nothing" is a self contradiction.

Agreed; I’m always looking for better ways to express that idea.

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Excellent point.  Especially if it's phrased as 'existing conditions'.

Thanks.  If the conditions were not “existing”, they would not exist, so there would be no conditions.  Right?

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I don't claim to be discussing science in this thread.

I’m not sure where the dividing line between science and semantics might be in this thread, but it is still throwing up some interesting stuff.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 24/10/2019 13:16:31
Archangel; I have, so far, only skimmed through your posts, but I plan to return for a better look.  I suspect that much of what you say would fit well with Bohm’s implicate/explicate orders.  If so, is that intentional?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 24/10/2019 17:25:22
There are other interpretations like QBism which are difficult to categorize but they are truly metaphysical.
Most interpretations are metaphysical. Copenhagen was originally intended as an epistemological interpretation, but some take it as a metaphysical description.

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Many-worlds is 1-B, the hidden variables are the other branches.
You grossly misrepresent the interpretation. It is not 1-B. Everett's paper lists only one postulate:

All isolated systems evolve according to the Schrodinger equation.

There are no hidden variables in there and it is entirely deterministic (no randomness). All the rest is corollaries. It is the essence of simplicity.
Unlike De Witt's take on MWI, Everett's MWI does not postulate that at certain magic instances, the the world undergoes some sort of metaphysical “split” into branches.

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The thing is, there is no reason to believe randomness is fundamental.
I agree here, and hold no such beliefs myself, but you've not falsified such interpretations. Anyone who believes in any interpretation to the exclusion of others is exercising faith based on what would probably be seen as weak and incomplete arguments by those holding a different belief.

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I am ready to bet anything you like on the fact that Quantum Gravity theory will only be achieved within a realistic theory demonstrating that randomness is emergent.
A quantum gravity theory probably will not resolve the QM interpretation issue.  It might cull out a few of them.  I doubt that all the randomness interpretation will be thus culled out (I'd take your bet in other words). The Schrodinger equation will need editing since the current one does not describe gravitational effects.

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Superposition being real is a belief. It is a mathematical equation.
No, it's a real demonstrated fundamental thing, not even something asserted by interpretations. It might be described by a mathematical equation. The orbit of Earth is similarly described by a mathematical equation, but that doesn't mean that the Earth doesn't actually orbit the sun.
This seems to be a point of difference in our opinions.  I'm talking about what is, and you're talking about how we describe it. Physics worked long before anything came along that understood and described it.  I'm talking about that physics, not the description of it.

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I think I've said enough to at least demonstrate that a causal theory with randomness as being emergent is not only possible but probable.
Not just probable.  Most interpretations deny intrinsic randomness, so their probability of existence is 100%. In fact, I'm not even sure which ones posit intrinsic randomness. Possibly the metaphysical Copenhagen interpretation I mentioned above.  It's hard to find a formal description of it because it seems to vary from one person to the next.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 24/10/2019 18:14:07
Quote from: Halc
No energy is needed for virtual pair production since they have zero mass/energy.
 
Shouldn’t that be zero net mass/energy?  If so, that’s quite different.  If something has no mass and no energy, in what sense does it exist?
Yea, zero net, and yes, they don't really exist yet, hence being virtual particles instead of real ones. Separating virtual particles might yield positive energy to one and negative to the other such that the positive one might become real, just like Pinocchio.

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It’s that “total/net” dichotomy again.
Is there a difference?  If I have objects with -3, -2, 1, 4 energy respectively, that's a net of zero and a total of zero, no?  Perhaps I'm missing the difference here.

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“Zero-energy universe. The zero-energy universe hypothesis proposes that the total amount of energy in the universe is exactly zero: its amount of positive energy in the form of matter is exactly canceled out by its negative energy in the form of gravity.”
Unless you say that positive energy = nothing, and negative energy = nothing, the “zero” must refer to net energy, not total energy.
Don't understand.  -5 + 5 = 0 total, not just 0 net.  Anyway, your quote identifies it as hypothesis.  We don't actually have a measurement of the total, or more meaningfully, the energy density of the universe.  I computed it once and got a very negative number, but then I probably did one or both sides wrong.

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….the whole phrase "ever has been nothing" is a self contradiction.

Agreed; I’m always looking for better ways to express that idea.
Just don't say 'come from'.  It implies an act of creation within something, in which case it just begs why the something it is within exists.

I found the best way to phrase it is not to say it at all, since it begs premises which I do not hold. The inability to phrase it correctly is a huge clue that it's contradictory and that there is a bias which needs to be reconsidered.  That's really hard to do, and I've only done it a couple times.

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If the conditions were not “existing”, they would not exist, so there would be no conditions.  Right?
That's right, but not necessarily the point. The point is that 'conditions' is a poor example of 'nothing'.

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I don't claim to be discussing science in this thread.
I’m not sure where the dividing line between science and semantics might be in this thread, but it is still throwing up some interesting stuff.
If your idea makes a testable prediction, it's science. I don't think anything I've said qualifies along those lines. I'm reaching for logic more than say physics.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 24/10/2019 18:27:33
It’s that “total/net” dichotomy again.
With food, a can of beans might say "Net wt. 430g" meaning it is the weight of the food, not including the can, and total weight would be perhaps 500g.  So the net is <not including the parts that don't matter (the can)>. When computing the mass of the universe or the mass of virtual partcles, everything matters, so there is no can, so the net and total are the same.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 24/10/2019 21:31:46
Archangel; I have, so far, only skimmed through your posts, but I plan to return for a better look.  I suspect that much of what you say would fit well with Bohm’s implicate/explicate orders.  If so, is that intentional?

That was my own conclusion a while ago (if you look at my theory). Contrary to Bohm's interpretation, consciousness, if produced by entanglement, would not be outside the brain but it would be the spatial complement to the space-time causal connections. This would be a synthetic image resulting from the brain of our perception which would include our current memory feed backs.

The idea comes from the current interpretation of entanglement mixed with a hidden variables theory. All classical forces decrease with the distance. The current interpretation of entanglement does not follow that law.

The problem is the detector is included in the wave function parameters but the mechanism of the particle being entangled with it is not explicit. As long as we don't have a good description of the mechanism, it is difficult to draw a conclusion. Some experimental setups may induce non-causal correlations while being interpreted as entangled states. I still think there are real entanglement relations though. There are quantum computers and encryption processes using entanglement. If it is useful, there is a reality to it. I doubt that electricity and gravity have entanglement relations which break the law of distance but magnetism could. Entanglement comes from the quantization of energy. In my theory, there are only space and time, and its dynamics.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 24/10/2019 22:06:39
Halc, the proponents of the MWI don't see it as a causal set but that is truly what they are thriving for. The use of the Schrödinger equation doesn't change anything for that matter. The problem with the MWI is that it replaces our own world relations with inter-worlds relations, moreover, with an exponential growth of new worlds created.

Concerning superposition, you are basically right that it is a matter of belief. Napoleon lost the battle of Waterloo: it is a belief. But not all beliefs have equal value. Superposition is all the possible results given by a probability distribution (the square of the function). But only one result is measured. Show me an example in real life where the probability distribution is real in regards to a single possibility that was measured as real. The probability distribution may be made of facts but they are never the properties of a single elements. For example, you may make a distribution by asking blindly the age of each student in a class and then try to guess the age of a specific student. But each student has only a single age.

Superposition being real is not a small leap of faith...
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 25/10/2019 11:30:53
Quote from: Halc
No energy is needed for virtual pair production since…….they don't really exist….

That makes sense. 

Matt Strassler says  “A virtual particle is not a particle at all. It refers precisely to a disturbance in a field that is not a particle.”

What causes the disturbance?

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Is there a difference?  If I have objects with -3, -2, 1, 4 energy respectively, that's a net of zero and a total of zero, no?  Perhaps I'm missing the difference here.

You could be, but if so, you are in good company.  John Barrow says: “Mathematical ‘existence’ meant only logical self-consistency and this neither required nor needed physical existence to complete it.  If a mathematician could write down a set of non-contradictory axioms and rules for deducing true statements from them, then those statements would be said to ‘exist’.” 

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I'm reaching for logic more than say physics.

Let’s look at “If I have objects with -3, -2, 1, 4 energy respectively”.
 They are objects; an object is not nothing, whether you choose to place a minus or plus sign in front of the number you assign to it. 
(-3)+(-2) = -5 = a quantity of energy = something.
(+1)+(+4) = +5 = a quantity of energy = something.
Neither is “nothing”. Only if you claim that one is “less than nothing” can this begin to make logical sense, and what can be less than nothing?  Vernacular expressions notwithstanding.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 25/10/2019 13:57:00
Matt Strassler says  “A virtual particle is not a particle at all. It refers precisely to a disturbance in a field that is not a particle.”

What causes the disturbance?
The disturbance is a valid solution to the field equations.  I don't think that it can be said to have a cause.  QM is full of uncaused events.

Quote from: Halc
Is there a difference?  If I have objects with -3, -2, 1, 4 energy respectively, that's a net of zero and a total of zero, no?  Perhaps I'm missing the difference here.
I was not talking about the difference between existence or not here. I was talking about the difference between net and total.

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John Barrow says: “Mathematical ‘existence’ meant only logical self-consistency and this neither required nor needed physical existence to complete it.
That is an amazingly good summary of my personal philosophy.

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If a mathematician could write down a set of non-contradictory axioms and rules for deducing true statements from them, then those statements would be said to ‘exist’.”
Writing them down seems to give them physical existence.  According to Barrow above, that is an unnecessary step.

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Let’s look at “If I have objects with -3, -2, 1, 4 energy respectively”.
 They are objects; an object is not nothing, whether you choose to place a minus or plus sign in front of the number you assign to it. 
(-3)+(-2) = -5 = a quantity of energy = something.
Yes, something.  So I have a basket of 5 apples, and I drop an negative apple of mass -1apple (something) into it, and now I have a basket of 4 apples (fewer somethings).  Objects of negative mass are mathematically possible, but no known stable instance of it has been found, but the prevailing theory is that's how you get rid of the apples from a basket (black holes) from which nothing can be removed.  I don't understand the theory behind it.  To me, it would seem that given a particle pair which manage to acquire positive and negative mass respectively, it would be the positive one that would fall in, not the negative one.  But I'm not a quantum physicist, so my understanding doesn't count.  Black holes spewing negative mass would be interesting indeed.  It would be a way of sucking in all the matter without having to wait for it to fall in.

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Neither is “nothing”.
Not claiming that zero is nothing.  I can have zero angular momentum, but that's quite different from not having an angular momentum.

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Only if you claim that one is “less than nothing” can this begin to make logical sense".
Eww, no.  -1 is less than 0, but no number is less than not-a-number.  That relation makes no sense.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 25/10/2019 14:36:03
Halc, the proponents of the MWI don't see it as a causal set but that is truly what they are thriving for. The use of the Schrödinger equation doesn't change anything for that matter. The problem with the MWI is that it replaces our own world relations with inter-worlds relations, moreover, with an exponential growth of new worlds created.

Concerning superposition, you are basically right that it is a matter of belief. Napoleon lost the battle of Waterloo: it is a belief. But not all beliefs have equal value. Superposition is all the possible results given by a probability distribution (the square of the function). But only one result is measured. Show me an example in real life where the probability distribution is real in regards to a single possibility that was measured as real. The probability distribution may be made of facts but they are never the properties of a single elements. For example, you may make a distribution by asking blindly the age of each student in a class and then try to guess the age of a specific student. But each student has only a single age.

Superposition being real is not a small leap of faith...
What parts of this I can parse seem to be personal assertions and things that are just plain wrong.  The rest just needs some vinaigrette. Thank you for your time, but I'm bailing out on this particular track.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 25/10/2019 17:42:49
Quote from: Halc @ https://www.thenakedscientists.com/forum/index.php?topic=76229.msg568400#msg568400

How is the dimensionless point at x=3, y=4 not have a location?  3, 4 (relative to the origin) is its location.

Of course, we’ve been here before.  The dimensionless point has a mathematical “location” which you identified, but, physically, what would you find at that location?  How could this dimensionless “concept” have any physical substance?  Perhaps it could be reasoned that whatever this is, is pure energy. Would that require dimensions in which to “exist”?  Possibly it could be claimed that it would not, but location “3,4” still has no dimensions, so it is “there” only in principle.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 25/10/2019 20:34:23
Quote from: Halc @ https://www.thenakedscientists.com/forum/index.php?topic=76229.msg568400#msg568400
How is the dimensionless point at x=3, y=4 not have a location?  3, 4 (relative to the origin) is its location.

Of course, we’ve been here before.  The dimensionless point has a mathematical “location” which you identified, but, physically, what would you find at that location?  How could this dimensionless “concept” have any physical substance?  Perhaps it could be reasoned that whatever this is, is pure energy. Would that require dimensions in which to “exist”?  Possibly it could be claimed that it would not, but location “3,4” still has no dimensions, so it is “there” only in principle.
Well, you're not going to find a macroscopic object there since they're not dimensionless. So how about an electron? It's not like any fundamental thing has ever been found with actual volume. That fact is strong evidence that matter is fundamentally mathematics, without any classic physicality that otherwise seems so intuitive.

I can't go so far as to say an electron is 'there' but it might be measured (to arbitrary precision) at that location.  If it is thus accurately measured, it certainly wouldn't be found there when you measured a second time.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 26/10/2019 17:03:22
Quote from: Halc
Well, you're not going to find a macroscopic object there since they're not dimensionless.

My point exactly.  You can assign a location, in principle, to a dimensionless “object” or location, but you will not find it in the physical world. 

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So how about an electron?

My understanding is that the electron has a rest energy of about 0.511 MeV, so it is not a dimensionless point; in fact, it is not a point at all.

When an electron is detected, what is seen is a small but fuzzy spot on a phosphorescent screen. Looked at with a high enough resolution, this spot becomes a diffraction pattern. Thus, empirically, it is a ‘bunched’ wave rather than a discrete particle.  Even this “wave packet” has dimensions, otherwise it would not be observable. 
How do you equate observing an electron with finding a measurable object in a dimensionless “location”? 
Possibly such was not your intention, but in that case, how is your response relevant to the questions in #206?
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That fact is strong evidence that matter is fundamentally mathematics,

I see that as an unwarranted assumption.  Undoubtedly, mathematics is the best tool we have devised for the study and understanding of our Universe, but assigning fundamentally to mathematics is tantamount to claiming intelligent causality.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 26/10/2019 19:52:00
My understanding is that the electron has a rest energy of about 0.511 MeV, so it is not a dimensionless point; in fact, it is not a point at all.
How is a property of rest energy in any way an expression of nonzero volume?  And I didn't say an electron was at a point, but I said it could be measured at one.  It is at a point under certain interpretations, but not others.

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When an electron is detected, what is seen is a small but fuzzy spot on a phosphorescent screen.
A fuzzy spot doesn't sound like a very accurate measurement.  Sounds like a measurement of the average field generated by electrons tied to say an atom, a very low precision measurement of an atom, not an electron.  Atoms definitely are not points and appear as fuzzy spots.  A high precision measurement (of of the electron's location) would impart immense momentum to the electron sending it off to parts unknown.  It would not be represented as a fuzzy spot, but rather as numeric coordinates.
Measuring its dimensions isn't possible because no known model gives it any.

Does any of this matter to the point in question?  I mean, if you want to think of an electron as a spherical object or 'bunched wave' with volume, does that change some critical part of the question of how existence exists?  I'm fine with you modelling them that way, despite lack of it making an empirical difference.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 26/10/2019 20:27:36
I googled "dimensions of an electron" and got some very contradictory answers.

alternativephysics: 2.82e-15, about 2.5x the dimensions of a proton, "based on an assumption that the mass-energy potential of an electron is fully contained within a certain radius, by equating E=mc² to E=ke²/r"  Except the latter r seems to be the radius from the center of an atom, not the radius of the electron.

I see this figure in wiki as well, and says this value is just a useful figure that "characterizes electron interactions in atomic-scale problems".  It says just above that "According to modern understanding, the electron is a point particle with a point charge and no spatial extent."

hypertextbook : Lists several sources:

https://gravityandlevity.wordpress.com/2015/04/11/how-big-is-an-electron/ gives a thorough discussion on the subject :
Quote
There is no concept of an electron size other than the spatial extent of the electron wavefunction.  The size of the electron wavefunction is the electron size.
This opinion essentially amounts to telling someone that they need to stop trying to think about a quantum electron as a physical object that you could hold in your hand like a baseball if only it was enlarged 10^{10} times.  People who profess this opinion are presumably also the ones who get annoyed by the popular declaration that “matter is 99.999% empty space.
That's one answer.  The next one models the electron as a ball of spatially separated material (not as a point) and calculates the minimum radius below which the energy needed to push the repelling parts together into an object would exceed the mass of the electron, which would be something around 10e-15m.

I encourage the reading of the whole thing, but my point in the prior post stands: I don't see the relevance to the discussion at hand.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Colin2B on 27/10/2019 06:09:26
When an electron is detected, what is seen is a small but fuzzy spot on a phosphorescent screen. Looked at with a high enough resolution, this spot becomes a diffraction pattern. Thus, empirically, it is a ‘bunched’ wave rather than a discrete particle.  Even this “wave packet” has dimensions, otherwise it would not be observable. 
What you are seeing here is not a picture of an electron. The high energy electron beam hitting the phosphor ejects electrons from the atom from the conduction band and the exciton band and it is these recombining with other atoms in the lattice which give the scintillations we see and hence the fuzzyness. We are not directly viewing an image of an electron or any sort of ‘bunched wave’.
Any claimed image of an electron needs to be examined carefully to determine just what was imaged and how as they are often not what is headlined in the popsci article. Can you provide link to what you are quoting, I would be interested to see it.

I agree with @Halc as I can’t see what electron rest energy has to do with its size. What is sometimes quoted as size is the probability ‘cloud’ or orbital around the nucleus.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 27/10/2019 15:36:38
Quote from: Halc
How is a property of rest energy in any way an expression of nonzero volume?

Because the electron volt is also a measure of mass.  I think mass usually involves volume.

Quote
Does any of this matter to the point in question?

Probably not, but I am loath to miss a learning opportunity. :)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 27/10/2019 15:48:10
Quote from: Colin
Can you provide link to what you are quoting, I would be interested to see it.

I’ve been hunting for it, without success.  I wanted to reread it myself.  On reflection, I think it must have come from a book or article, rather than online.  My original note is all I can find, and I’m fairly sure I was waiting for my son in Hosp. when I wrote it; so no online access.  This is all I have.  I quote it in case anyone recognises it, or can trace it.

Quote
12.02.15.    It should be mentioned that  when the electron is claimed to be seen as a particle, as in J. J. Thomson’s cathode ray experiment, it is not really seen as a truly discrete (point) particle — this is impossible. What is seen is a small but fuzzy spot on the phosphorescent screen. If one should look into this spot with a high enough resolution, a diffraction pattern would be seen inside of it. Thus, this is, empirically, a ‘bunched’ wave and not a discrete particle in the first place.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 27/10/2019 17:00:15
Quote from: Halc
How is a property of rest energy in any way an expression of nonzero volume?
Because the electron volt is also a measure of mass.  I think mass usually involves volume.
A measure of mass, yes, but mass does not necessarily involve volume. A finite density would be required, and a point mass has no meaningful density.
Quote
Quote
Does any of this matter to the point in question?
Probably not, but I am loath to miss a learning opportunity. :)
Let's go with a proof then.

P1 X is a fundamental particle
P2 X occupies volume (or space in at least one dimension)
C1 The material of X on one side is spatially separated from the material of X on the other side.
C2 X is comprised of the two chunks of material on one side and the other (X is made of parts)
C3 X is not fundamental.

P1 and C3 are contradictory, thus at least one of the premises is false.


Quote
it is not really seen as a truly discrete (point) particle — this is impossible
It is impossible for a classic object made of parts, yes, but classic intuitions don't apply at this scale. He hasn't exactly demonstrated why it is impossible for something fundamental.  He seems to be describing its effect on said screen, and not the electron itself.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 27/10/2019 17:29:19
Because the electron volt is also a measure of mass.  I think mass usually involves volume.
A photon has eVs of energy but no mass. E certainly = mc^2 but you can't have your cake and eat it!
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 27/10/2019 17:31:51
The notion that "fundamental" particles are composed of quarks is a good model but until someone actually observes a quark, the proton and electron remain fundamental.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 27/10/2019 17:47:28
Quote from: Halc
A measure of mass, yes, but mass does not necessarily involve volume. A finite density would be required, and a point mass has no meaningful density.

It has no meaningful density, because that is how it is defined in principle, and this definition has value in the appropriate context. Only if you differentiate, clearly, between “meaningful density” and “density” can it have any physical significance.

What is the difference between “density” and “meaningful density”?

Quote
P1 X is a fundamental particle
P2 X occupies volume (or space in at least one dimension)
C1 The material of X on one side is spatially separated from the material of X on the other side.
C2 X is comprised of the two chunks of material on one side and the other (X is made of parts)
C3 X is not fundamental.

P1 and C3 are contradictory, thus at least one of the premises is false.

The logic is good, as it stands, but if a fundamental particle is (as far as current knowledge accepts) one that cannot be divided into lesser parts, this does not preclude its having mass.  Indeed, The Higgs field gives mass to fundamental particles.  So some refinement might be needed to guarantee that C3 was an accurate conclusion.

Mass is the amount of matter an object contains, and volume is the space it takes up.  Only if you can provide a physical example of a volumeless mass is your reasoning anything other than hypothetical.

Chris Baird has a relevant comment at:  https://wtamu.edu/~cbaird/sq/2014/02/07/what-is-the-shape-of-an-electron/

Quote
If you find the concept of a fixed amount of mass being contained in the infinitely small volume of a single point illogical, then you should. But you have to realize that the electron is not literally a solid ball. This means that the electron's mass is not literally squeezed into an infinitely small volume. Rather, in certain cases where the electron looks somewhat like a particle, it interacts as if it were completely located at a single point.
 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 27/10/2019 17:56:27
Sorry, Alan; we crossed over, there.

Quote
you can't have your cake and eat it!

By now, you should realise that won't stop me from trying. :)

BTW, my mother used that expression, and I always thought it should have been "...eat your cake and have it".
I guess I must have been a pedantic kid. :(

Duty calls, and your comments need some thought before trying a more serious reply.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 27/10/2019 18:11:31
A photon has eVs of energy but no mass.
A photon very much has mass (and inertia, and everything that goes with mass). It only lacks proper mass, but it also lacks proper energy, so it's still consistent.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 27/10/2019 18:18:18
You are confusing inertia with momentum. A lump of rock at rest has inertia (you need to do work to move it) but no momentum. A photon can transfer momentum but has no inertia.

Bill isn't the only one born pedantic. There's still hope that he will become a physicist - just keep polishing that pedantry!
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 27/10/2019 19:05:24
Quote from: Alan
A photon has eVs of energy but no mass. E certainly = mc^2 but you can't have your cake and eat it!

Quote from:   https://www.quora.com/How-does-E-mc2-explain-that-light-has-mass
Let's try to phrase this another way. What is the meaning of the equation E=mc2? You can interpret it to mean that energy is the same thing as mass except for a conversion factor equal to the square of the speed of light. Then wherever there is mass there is energy and wherever there is energy there is mass. In that case photons have mass, but we call it relativistic mass. Another way to use Einstein's equation would be to keep mass and energy as separate and use it as an equation which applies when mass is converted to energy or energy is converted to mass--usually in nuclear reactions. The mass is then independent of velocity and is closer to the old Newtonian concept. In that case, only the total of energy and mass would be conserved, but it seems better to try to keep the conservation of energy. The interpretation most widely used is a compromise in which mass is invariant and always has energy so that total energy is conserved but kinetic energy and radiation does not have mass. The distinction is purely a matter of semantic convention.


“Physicists deftly shift between different pictures of reality as it suits the task at hand.”

https://aeon.co/essays/is-everything-made-of-particles-fields-or-both-combined?utm_source=Nature+Briefing&utm_campaign=33b07f7e21-briefing-wk-20191025&utm_medium=email&utm_term=0_c9dfd39373-33b07f7e21-42120079

Quote
The notion that "fundamental" particles are composed of quarks is a good model but until someone actually observes a quark, the proton and electron remain fundamental.


I have no problem with fundamental particles as being indivisible, just with the idea that they might have mass (as per Higgs) but not occupy volume. Light seems to be a special case, in more ways than one, but although it is well established that light has no rest mass, the question of “definitions” seems to roll on: The thread at

https://www.thenakedscientists.com/forum/index.php?topic=8298.0  is even longer than this one.

Quote
There's still hope that he will become a physicist 

Thanks, Alan. I admire your optimism.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 27/10/2019 19:22:15
Quote from: Halc
A measure of mass, yes, but mass does not necessarily involve volume. A finite density would be required, and a point mass has no meaningful density.
It has no meaningful density, because that is how it is defined in principle, and this definition has value in the appropriate context. Only if you differentiate, clearly, between “meaningful density” and “density” can it have any physical significance.
Well, density is a function of the mean separation of the components, and if there is but one component, there is nothing with which it is separated. It's the same way velocity has no meaning without a reference.

Quote
What is the difference between “density” and “meaningful density”?
Kind of like the difference between distance and meaningful distance.  It is meaningful to say Bob is 5 meters distant from Alice, but it isn't meaningful to say Bob is 5 meters distant.  Takes two to tango.  There is a crowded (not particularly bounded) dance floor with a 0.5 meter mean distance between dancers.  That's a statement of density.  One dancer defines no meaningful density since there is no separation from another dancer.

Quote
Quote
P1 X is a fundamental particle
P2 X occupies volume (or space in at least one dimension)
C1 The material of X on one side is spatially separated from the material of X on the other side.
C2 X is comprised of the two chunks of material on one side and the other (X is made of parts)
C3 X is not fundamental.

P1 and C3 are contradictory, thus at least one of the premises is false.

The logic is good, as it stands, but if a fundamental particle is (as far as current knowledge accepts) one that cannot be divided into lesser parts.
Totally agree, but if I can speak of its left half and right half, then I'm talking about separate parts despite my presumed lack of technology to separate them.  Quarks don't stand on their own either, but the quarks comprising a proton do not occupy the same location and have a measured mean separation.  A proton thus has density.

Quote
This does not preclude its having mass.  Indeed, The Higgs field gives mass to fundamental particles.  So some refinement might be needed to guarantee that C3 was an accurate conclusion.
The proof didn't reference anything like energy, mass, or electrons.  It's just something that can be applied to anything one suggests is fundamental.

Quote
Mass is the amount of matter an object contains, and volume is the space it takes up.
Ouch.  I have never seen that definition of mass. It is incompatible with physics. Matter can be created and destroyed, but mass cannot. They're different things.  Volume is indeed the space something takes up. I'm suggesting a fundamental thing doesn't take up any space since there is no distance to something else from which it must separate itself.

Quote
Chris Baird has a relevant comment:
Quote
If you find the concept of a fixed amount of mass being contained in the infinitely small volume of a single point illogical, then you should. But you have to realize that the electron is not literally a solid ball. This means that the electron's mass is not literally squeezed into an infinitely small volume. Rather, in certain cases where the electron looks somewhat like a particle, it interacts as if it were completely located at a single point.

OK.  Opinions vary.  I notice he doesn't suggest an alternative or explain why it isn't logical, but rather speaks of its interactions, which seems to be from where all the 'radius' calculations given seem to be drawn. With that I agree. Just because it doesn't take space doesn't mean you can (easily) push two of them closer than a certain distance.  It's the same reason I cannot park two cars in the same parking space. Sure, that much matter is allowed there, but the forces preventing it are usually larger than the forces attempting it.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: yor_on on 27/10/2019 19:45:27
I don't think the classical model holds. In a quantum mechanical model I understand it as probabilities. Statistical proofs until a outcome sort of.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Hayseed on 27/10/2019 21:23:42
The improved and updated Parson Magneton model presents a physical causation of all particle measured properties.  And a most temping path for the causation for gravity.

And it takes all probability out of any state.   It also explains the physical dynamic of light and disproves space-time.

UN-modulated nature has no probability or randomness.

Life is the modulator.  And it does not add probability or randomness.....it adds choice.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 27/10/2019 22:30:12
Quote from: Halc
The proof didn't reference anything like energy, mass, or electrons.  It's just something that can be applied to anything one suggests is fundamental.

Wouldn’t “anything one suggests is fundamental” include fundamental particles? The quote to which you are responding:
Quote
This does not preclude its having mass.  Indeed, The Higgs field gives mass to fundamental particles.  So some refinement might be needed to guarantee that C3 was an accurate conclusion.
mentions only fundamental particles.

Quote
  I have never seen that definition of mass. It is incompatible with physics.

Dr. Helmenstine Ph.D. disagrees, but perhaps her Ph.D. is in the wrong subject. 

https://www.thoughtco.com/difference-between-mass-and-volume-609334

Quote
Mass and volume are two units used to measure objects. Mass is the amount of matter an object contains, while volume is how much space it takes up.

Quote from: Halc
  I'm suggesting a fundamental thing doesn't take up any space since there is no distance to something else from which it must separate itself.


I’m struggling to equate that to any physical object.  A little help, please.

Quote from: Baird
This means that the electron's mass is not literally squeezed into an infinitely small volume.

Does your analogy address this, or does it refer to something else Baird said?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 27/10/2019 23:48:25
Quote from: Halc
The proof didn't reference anything like energy, mass, or electrons.  It's just something that can be applied to anything one suggests is fundamental.
Wouldn’t “anything one suggests is fundamental” include fundamental particles? The quote to which you are responding:
Quote
This does not preclude its having mass.  Indeed, The Higgs field gives mass to fundamental particles.  So some refinement might be needed to guarantee that C3 was an accurate conclusion.
mentions only fundamental particles.
I was responding to the part I bolded. I made no conclusion or even mention in my little 'proof' concerning mass, so yes, it doesn't preclude it, and no refinement is needed for mass which wasn't part of the logic.

Quote
Quote from: Halc
Quote
Mass is the amount of matter an object contains
I have never seen that definition of mass. It is incompatible with physics.
Dr. Helmenstine Ph.D. disagrees, but perhaps her Ph.D. is in the wrong subject. 

https://www.thoughtco.com/difference-between-mass-and-volume-609334
Quote
Mass and volume are two units used to measure objects. Mass is the amount of matter an object contains, while volume is how much space it takes up.
I guess that works in Newtonian days, but an electron meets a positron and the matter vanishes, but the mass does not, so the mass that remains behind is not the amount (zero) of matter contained by the resulting system.

Similarly, one can consider a 1kg object in a frame where it is moving at a high percentage of light speed, and it gains no matter (same number of everything), but it gains arbitrary mass.  Mass is frame dependent (not a property of the object) and 'amount of matter' is a property and not frame dependent. So with kind respects to Helmenstine's Ph.D, her statement is not precise in the general case. The statement works for high-school physics but not a class in relativity or quantum mechanics. The purpose was to distinguish between the two terms, and not to provide precise definitions of either.

Quote
Quote from: Halc
  I'm suggesting a fundamental thing doesn't take up any space since there is no distance to something else from which it must separate itself.

I’m struggling to equate that to any physical object.  A little help, please.
Well just think of a mathematical plane with some points in it.  What is the density (or volume) of one point?  Both are undefined, since the terms concern relations between the elements.  But given two point, there becomes a rudimentary density (average separation of points), and a distance between them.  3 points might define area, and 4 define volume.

So take a thousand such points in 3D space and give each one a weight (a number representing proper mass).  Shrink a surface that encloses all the points and a clear volume appears.  We now have an object with volume, mass, and density, the latter which is expressed as total mass over total volume. Volume and density emerge from a set of points none of which by itself has either property.

Quote
Quote from: Baird
This means that the electron's mass is not literally squeezed into an infinitely small volume.
Does your analogy address this, or does it refer to something else Baird said?
Baird didn't show the 'illogical' that he asserts.  I agree that the electron's mass is not litterally squeezed into a small volume since squeezing implies more fundamental components being forced together.  Also, 'infinitely small' is a way to bias the reader against the concept that could be expressed simply as 'zero'.  He makes it sound like it is impossible for a basket to contain no apples by wording it as "the basket would have to contain an infinitely small quantity of apples".

Hey, maybe I'm just wrong.  Everybody seems to be running from intuition born of classic objects, and that's not the way to address these questions. I am unimpressed by credentials if these guys can't say what premises are being assumed in the making of these assertions.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Colin2B on 28/10/2019 00:24:52
On reflection, I think it must have come from a book or article, rather than online. 

https://books.google.co.uk/books?id=wh9qDQAAQBAJ&pg=PA53&lpg=PA53&dq=It+should+be+mentioned+that++when+the+electron+is+claimed+to+be+seen+as+a+particle,+as+in+J.+J.+Thomson’s+cathode+ray&source=bl&ots=DPLwcniFcq&sig=ACfU3U3J926MkvlNlmtxXLIc6QevcdmrmA&hl=en&sa=X&ved=2ahUKEwjFgc2bwr3lAhWHh1wKHeo2AJEQ6AEwDnoECAoQAQ#v=onepage&q=It%20should%20be%20mentioned%20that%20%20when%20the%20electron%20is%20claimed%20to%20be%20seen%20as%20a%20particle%2C%20as%20in%20J.%20J.%20Thomson’s%20cathode%20ray&f=false

Book by Mendel Sachs. Did a lot of good work but tried to develop his own unified theory, believed time dilation/differential ageing is not real, predicted search for Higgs would be a waste of time, mainly because it conflicted with his own ideas.
Interesting he uses word ‘should’ (you) look into this spot, rather than ‘if’ so I think he is speculating and doing so incorrectly. Clearly he didn’t understand the crt. The reason for the fuzzy spot is that, as I explained before, you are not looking at the image of a single electron. The electron beam has a specific width of x electrons which due to their charge begin to diverge, so the density of electrons in the beam cross-section is greater in the centre than at the edges - hence fuzzy at edges where fewer photons are released by the phosphor. No diffraction pattern or wave bunch.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 28/10/2019 00:50:35
The uncertainty principle shows that if you want to measure the energy or momentum of a particle, you have to measure it over a minimum of time corresponding to the Compton wavelength of the particle at the speed of light which gives you uncertainty on time and position. According to the uncertainty principle, if the size of an electron is equal or smaller than its Compton wavelength, it is impossible to know its size. The size of a proton is larger than its equivalent Compton wavelength.

The momentum of a photon may be interpreted as a relativistic inertia as you will be pushed by it when you stop it. But it is a priori entirely relativist unless you take account of the entire Universe where you may possibly obtain a non-vanishing but still relativistic mass.

What Alan said about the proton and the quarks is very interesting. Quarks are supposed to be elementary particles but no quark has ever been observed directly. Is the proton an elementary particles or were quarks separated in the early universe?


Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 28/10/2019 07:41:58
I can't accept such misuse of a well-defined word. Inertia is
Quote
a property of matter by which it continues in its existing state of rest or uniform motion in a straight line, unless that state is changed by an external force.


Inertia has the dimension [M].

Momentum has the dimension [M][L][T]-1.

Knowing the gyromagnetic ratio, magnetic moment, mass and charge of a stationary electron (all measurable), we can calculate an effective radius. Just one example of why it is important to distinguish between uncertainty (experimental) and indeterminacy (inherent). 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 28/10/2019 08:28:50
As the strict definition is concerned, you are right but inertia is always measured with an exchange of momentum in reality. A photon has a relativistic mass. You can say its a relativistic inertial mass only in its direction of motion. I know that strictly speaking, it is not the same but in the end, it could be the same basic phenomenon and there are good reasons to think that way.

The calculation of an effective radius of an electron depends on the theory. It is the measurement which counts. It is a circular argument. Do you know that the maximum electric field you can measure for an electron is equivalent to a charge at a distance equal to its Compton wavelength divided by 2*pi? (at least for a slow electron)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 28/10/2019 09:25:47
As the strict definition is concerned, you are right but inertia is always measured with an exchange of momentum in reality.
Really? I just measured the inertia of a brick by comparing it with a standard mass on a beam balance. Nothing moved and there was no exchange of momentum. Momentum exchange was one method of measuring the speed of a bullet by firing it into a lead pendulum, but the inertia (i.e. the mass) of the pendulum was measured with a beam balance. 

Quote
A photon has a relativistic mass. You can say its a relativistic inertial mass only in its direction of motion.
You might say so, but as a committed physicist I would probably die rather than utter a meaningless phrase! Einstein's derivation of radiation pressure and photon momentum doesn't involve any solecisms.

Quote
The calculation of an effective radius of an electron depends on the theory.
That is implicit in the word "effective". 
Quote
Do you know that the maximum electric field you can measure for an electron is equivalent to a charge at a distance equal to its Compton wavelength divided by 2*pi? (at least for a slow electron)
That is entirely consistent with indeterminacy. Which is fortunate, to say the least!
Title: Re: Was the Big Bang the beginning of the universe?
Post by: CPT ArkAngel on 28/10/2019 09:58:45
No displacement in your balance? Inertia is opposition to motion. No motion, no inertia. In Einstein theory, it is a scalar while the momentum is vectorial. The photon is ill-defined in Einstein theory and the difference between the origin of inertia and momentum is not so obvious when you consider energy from a relativistic mass point of view. The momentum corresponds to mass.

see https://arxiv.org/abs/1909.09084
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 28/10/2019 11:50:25
Quote from: Halc
A photon very much has mass (and inertia, and everything that goes with mass).
You are confusing inertia with momentum.
Gravitational mass is the m in F=GMm/r² (that which gives weight on a planet), but inertia is the m in F=ma (that which gives weight on a ship under thrust).  Turns out the two are the same thing to as many digits as they can measure.  Momentum does not go with mass.  An object can have nonzero mass but zero momentum in a certain frame.
Inertia is a scalar, and momentum is a vector. Momentum is not a property of mass.  It is a relation mass has with a reference frame.
Quote
A photon can transfer momentum but has no inertia.
This would violate conservation of momentum (and energy) if true.

If a photon had no inertia, it would take no force to accelerate it (say via a mirror or bending around a gravity well).  If there was no force, there would be no change to momentum as the path changed.  I could get a photon to gain energy from the acceleration without that energy being taken from anything.  Energy for free!

The momentum of a photon may be interpreted as a relativistic inertia
...
Inertia is opposition to motion. No motion, no inertia.
That is indeed wrong.  The top statement seems to equate inertia to momentum, and the bottom one contradicts your own correct statement about momentum being vectorial.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 28/10/2019 14:27:59
 
Quote from: Halc
I was responding to the part I bolded.

OK with that. Just making sure I didn’t misinterpret you.

Quote
…. but an electron meets a positron and the matter vanishes, but the mass does not,

Presumably, because energy has mass, but no matter. (?)

Quote
What is the density (or volume) of one point?  Both are undefined, since the terms concern relations between the elements.  But given two point, there becomes a rudimentary density…

Quote
Volume and density emerge from a set of points none of which by itself has either property.

This works well, as long as you define a point as zero dimensional, but still existing as a physical object.

Quote
He makes it sound like it is impossible for a basket to contain no apples by wording it as "the basket would have to contain an infinitely small quantity of apples".
 

How are you distinguishing between zero and an infinitely small quantity?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 28/10/2019 15:53:54
Quote
…. but an electron meets a positron and the matter vanishes, but the mass does not,
Presumably, because energy has mass, but no matter. (?)
Yes, energy in some other form than matter.
A mechanical watch that has been wound masses more than the same watch that has run down.  Pretty trivial difference, but it is there.

Quote
Quote
Volume and density emerge from a set of points none of which by itself has either property.
This works well, as long as you define a point as zero dimensional, but still existing as a physical object.
If it has length or something, it isn't a point. Yes, I'm suggesting that fundamental physical objects have no dimensions, but QM says it is a stretch to assert that they actually 'exist' at a location (be they dimensionless or not). It only gives a location where it might be measured, but that's still a point. It doesn't say that a sufficiently accurate measurement will have it occupying a region from here to there.
I hold to the principle of locality, a principle which is inconsistent with a model that asserts that physical particles have a location. They only have a wave function which, if known, can be used to compute probabilities of where it might be found were one to measure it.
CPT ArkAngel I suspect holds to CFD principle, which asserts that fundamental things (again, dimensionless or not) have an actual location at any given time, and the wave function simply describes our limited knowledge of the full state. This is a rejection of locality, which means effect can precede cause, spooky action at a distance, and all that.

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He makes it sound like it is impossible for a basket to contain no apples by wording it as "the basket would have to contain an infinitely small quantity of apples".
How are you distinguishing between zero and an infinitely small quantity?
The latter sounds more dramatic, but they mean the same thing. I'm criticizing Baird's choice of words.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 28/10/2019 18:46:32
Thanks Colin; early 2015 is roughly when I would have been reading The Haifa Lectures; so that fits well. 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 28/10/2019 18:49:14
Quote from: Bill
How are you distinguishing between zero and an infinitely small quantity?

Quote from: Halc
The latter sounds more dramatic, but they mean the same thing.

How would you distinguish between zero and non-existent?   
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 28/10/2019 18:53:09
If a photon had no inertia, it would take no force to accelerate it (say via a mirror or bending around a gravity well).  If there was no force, there would be no change to momentum as the path changed.  I could get a photon to gain energy from the acceleration without that energy being taken from anything.  Energy for free!
So photon paths bend round a gravitational object (observed) and thus the photons gain energy. By depleting the mass of the object? Very interesting, and a whole new aspect of cosmology.

We know, from the Pound-Rebka experiment, that photons are blueshifted as they travel towards the Earth. They can't be gaining their energy from their source because the source doesn't know where the photon is going: if the Earth has a weaker gravitational field than the source, they would be redshifted and thus transfer energy back to the source! So they must be gaining their energy by depleting the mass of the Earth.  Really?

This is just one of the many areas where classical mechanics just doesn't work, my friend. Einstein's realisation was that energy density is dimensionally equivalent to pressure, so a box full of photons has an internal pressure on its faces, thus individual photons can transfer momentum to a reflector or absorber without having any mass. No mass = no inertia.

Inertia is a scalar, momentum is a vector. Gravitational lensing or blueshift is a change in a vector quantity, equivalent to the classical F = dp/dt where p is a momentum vector. It's very important to know and respect the difference between a vector and a scalar: 200 mph towards has a very different effect from 200 mph away from, and a stationary mass is very different from a moving one, or even a photon.

Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 28/10/2019 18:54:32
How would you distinguish between zero and non-existent?   
I have zero money. Money is non-existent on Mars.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 28/10/2019 20:34:31
How would you distinguish between zero and non-existent?
My sister is nonexistent.
I have zero sisters.

For me, existence is to be measured, so I can measure the count of my sisters, and it comes up zero. But the first wording is a reference to a specific person, and that reference does not correspond to anything, hence is nonexistent.
That seems to be the best distinction I can come up with.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 29/10/2019 11:09:30
Quote from: Alan
I have zero money. Money is non-existent on Mars.

In my current situation, money is non-existent.  As far as I am aware, there is zero money on Mars.

You can make it work both ways, if you really want to.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 29/10/2019 11:28:13
Quote from: Halc
My sister is nonexistent.
I have zero sisters.

For me, existence is to be measured, so I can measure the count of my sisters, and it comes up zero. But the first wording is a reference to a specific person, and that reference does not correspond to anything, hence is nonexistent.
That seems to be the best distinction I can come up with.


I see your distinction, but it is purely lexical semantics.  If we were discussing philosophy, it would be fine.
 
Consider the definition of non-existent at:

https://www.google.com/search?q=opposite+of+nonexistent&oq=opposite+of+nonexisent&aqs=chrome.1.69i57j0.14448j1j1&sourceid=chrome&ie=UTF-8

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not existing or not real or present

Your sister is non-existent, therefore, she is not real.
You have zero sisters, therefore, you do not have a sister who can be said to exist.
Both examples fall under this definition.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 29/10/2019 11:53:47
The money example is robust.

Having zero money implies that the concept of money has some meaning in context and that I could have a nonzero amount - the amount in my account  is a member of an extant and meaningful set - the sums of money owned by people on Earth.

The set of sums of money owned by people on Mars is non-existent and meaningless. There being no people there, the concept of money (i.e. the common property of the members of that set) is undefined, so the set does not exist. 

Neatly, this leads to a definition of money: the set of tokens that people exchange for goods and services. It covers every form of monetary exchange but it entirely reliant on the presence and consensual activity of humans.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 29/10/2019 14:11:18
Quote from: Halc
My sister is nonexistent.
I have zero sisters.

For me, existence is to be measured, so I can measure the count of my sisters, and it comes up zero. But the first wording is a reference to a specific person, and that reference does not correspond to anything, hence is nonexistent.
That seems to be the best distinction I can come up with.


I see your distinction, but it is purely lexical semantics.  If we were discussing philosophy, it would be fine.
 
Consider the definition of non-existent at:

https://www.google.com/search?q=opposite+of+nonexistent&oq=opposite+of+nonexisent&aqs=chrome.1.69i57j0.14448j1j1&sourceid=chrome&ie=UTF-8

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not existing or not real or present

Your sister is non-existent, therefore, she is not real.
You have zero sisters, therefore, you do not have a sister who can be said to exist.
Both examples fall under this definition.
Totally agree.  That is consistent with my usage of the words.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 29/10/2019 14:15:43
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The money example is robust.

One of the things I like about this thread is that it keeps introducing different perspectives.

What you say about the concept of money, and the introduction of sets is instructive. 

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this leads to a definition of money

Interesting stuff, but still throws no light on any difference there might by between zero and non-existent in terms of physical objects.

Sometimes I’m glad I’m not a mathematician!  Life is complicated enough, as it is.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 29/10/2019 14:23:06
That’s another thing I like about this thread; it’s possible for two posters to “Totally agree” when they seem to be disagreeing.  Perhaps we need a good definition of “agree”.  :)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 29/10/2019 15:26:13
I'm saying you're using the words correctly in your post. The words mean different things, which is easily illustrated by trying to swap them.

My sister is nonexistent.  My sister is zero.
I have zero sisters.  I have nonexistent sisters.

In both cases, the left side conveys the intended meaning and the right side doesn't, if it make sense at all.
Prisoner zero has escaped!
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 29/10/2019 16:47:26
Quote
My sister is nonexistent.  My sister is zero.
I have zero sisters.  I have nonexistent sisters.

That's why I didn't try to swap your statements.  However, doing so does highlight one point that is very relevant to the OP.
Saying there could ever have been "nothing" is not dissimilar from saying " I have nonexistent sisters".
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 29/10/2019 17:08:10
Interesting stuff, but still throws no light on any difference there might by between zero and non-existent in terms of physical objects.
I have zero apples. Unicorns are non-existent.

Or to be really, really pedantic: There are zero Indian elephants in my garden (because I've eaten all the apples). Martian elephants are non-existent.

This has important forensic consequences. There might be a lingering smell of elephant in a garden, or even a huge pile of sh1t, that would lead Poirot to unmask the murderer as a rogue mahout, and the defence "I was working the native elephants on Mars" is no alibi. 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 29/10/2019 17:56:04
Quote from: Alan
I have zero apples. Unicorns are non-existent.

I believe you, and have no problem with this distinction, in this context.

It still leaves me with the ongoing questions:

If something is infinitely small, does it, physically, exist?

Does the concept of "infinitely small" have any meaning? 

I know we can wander off into definitions of “exist” and various other terms; but am I the only one who sees a fundamental problem here?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 29/10/2019 18:08:53
If something is infinitely small, does it, physically, exist?

Does the concept of "infinitely small" have any meaning?
We've been over this.  It means zero size.
The center of gravity of Earth exists (is real and present), and lacks a nonzero dimension.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 29/10/2019 19:50:17
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The center of gravity of Earth exists (is real and present), and lacks a nonzero dimension.

Of course it is, but, but it exists only in that it is differentiated as part of the Earth.  It has no independent existence.

How big is its “nonzero dimension”? 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 29/10/2019 21:58:31
Quote
The center of gravity of Earth exists (is real and present), and lacks a nonzero dimension.

Of course it is, but, but it exists only in that it is differentiated as part of the Earth.  It has no independent existence.
All correct. The angular momentum of Earth similarly exists (and hasn't a location), and similarly does not exist independent of Earth.

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How big is its “nonzero dimension”?
I said it lacks one.  It is a point in space, or a worldline in spacetime.  The latter has a length of perhaps 12-13 billion light years.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 29/10/2019 22:49:33
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I said it lacks one.

Sorry, the question should have been: how big is a zero dimension?

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It is a point in space,

So, a zero dimensional entity has zero dimensions, and that is a point, which is also zero dimensional.  A trace of tautology, here, don’t you think?

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or a worldline in spacetime.  The latter has a length of perhaps 12-13 billion light years.

How can it be zero dimensional if it has length?    Wouldn't that be one dimensional?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 30/10/2019 00:42:47
Quote from: Halc
or a worldline in spacetime.  The latter has a length of perhaps 12-13 billion light years.
How can it be zero dimensional if it has length?    Wouldn't that be one dimensional?
A worldline (of a spatial point like the center of gravity of Earth) is a line in spacetime, yes.  It is one dimensional in that it has no width or anything, but it is 4 dimensional in that it isn't a straight line and thus follows 4 nonzero coordinates in its path.  A wiggly line on a planar graph is one dimensional (has no area), but still requires coordinates in two dimensions to describe.

Technically, the center of gravity of Earth moves around at faster than light speed, and thus its worldline is sort of broken instead of a nice continuous line.  This is because the material that constitutes Earth is not fixed.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 30/10/2019 00:55:19
Does the concept of "infinitely small" have any meaning? 
It's a poor phrase, be cause logically it means "Bigger than you can imagine small" "Infinitesimal" is the mathematical term you are looking for. 

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am I the only one who sees a fundamental problem here?
Apparently! Surely everyone else can distinguish between the local absence of stuff that could be present at a point, and the universal non-presence of stuff that couldn't. James and John are not at school today. James has a toothache. Thanks to effective contraception, John does not exist. Massive difference! The taxpayer has to buy desks for kids who happen to have a day off, but not for those who were never born.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 30/10/2019 13:47:51
Quote from: Halc
The center of gravity of Earth exists (is real and present), and lacks a nonzero dimension.

It “lacks a nonzero dimension”.  Sounds like a good explanation, but what does it mean?  If it lacks a nonzero dimension, then it must have “a zero dimension”.  Therefore, it occupies no space.  It is, in fact, the conceptual point at which the total mass of the Earth must be considered as residing, in order to work with Newtonian gravity.  I have no problem with that.

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I said it lacks one.  It is a point in space, or a worldline in spacetime. 

Just for clarity; a point in space lacks a non-zero dimension, so it is zero-dimensional; whereas a worldline lacks a non-zero dimension, but has, as you explain in #255, either one or four dimensions.  (?)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 30/10/2019 14:02:28
Quote from: Halc
The center of gravity of Earth exists (is real and present), and lacks a nonzero dimension.

It “lacks a nonzero dimension”.  Sounds like a good explanation, but what does it mean?  If it lacks a nonzero dimension, then it must have “a zero dimension”.
Yes, it does. All three of its spatial dimensions are zero.  It has zero length, width, and height.
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Therefore, it occupies no space.
Correct.
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It is, in fact, the conceptual point at which the total mass of the Earth must be considered as residing, in order to work with Newtonian gravity.  I have no problem with that.
Newtonian gravity doesn't require all mass to be a point.  He proved that the mathematics can be simplified to that case if the object is spherically symmetrical, which Earth almost is. But Newtonian gravity works fine for irregular objects. It just needs a longer pencil to work out.

Quote
Just for clarity; a point in space lacks a non-zero dimension, so it is zero-dimensional; whereas a worldline lacks a non-zero dimension, but has, as you explain in #255, either one or four dimensions.  (?)
The worldline of a point is still a mathematical (not straight) line, which has no thickness in any spatial dimension.  Earth is not a point, so it has a worldline that is some 11000km thick in any of the three dimensions, at least in a frame near that of Earth.  In other frames, some of those three values might be significantly less.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 30/10/2019 14:19:44
Lacking a nonzero dimension means having zero spatial (or spatiotemporal, or indeed any of the 256 dimensions that pay the rent for string theorists) extent in any direction. What it doesn't mean is "having zero dimensionality", because a point is defined by the confluence of vectors.

(x,y,z) is a point in 3D. Any or all of the coordinates can be zero, depending on where you assign the origin of the coordinates, and conventionally they all originate at (0,0,0). (1,2,3) obviously has dimensionality because we get to or from it by travelling through three dimensions. And if we started there, we could get to (0,0,0) without becoming spaghettified or losing any information, so (0,0,0) is a point with dimensionality but no spatial extent.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 30/10/2019 15:12:31
The center of gravity of Earth exists (is real and present), and lacks a nonzero dimension.
You should attack this more. I can think of counters to both assertions.

For one, nothing in physics acts on this center of gravity. That alone makes it questionably real.
For instance, take two stars whose mutual center of gravity just happens to fall in Earth's path.  Nothing will happen when Earth gets there since there's nothing actually there.

I already asserted that it moves faster than light. Real things can't do that.

About it being a point: The position of any particle is probably (most interpretations deny it) not real.  There is only a probability that it will be measured in a given place. Hence lacking position, a particle has no center of gravity and any center of gravity of a collection of such indeterminate particles is similarly indeterminate.  OK, the errors average out, but the center of mass of Earth is thus possibly from here to there.  It has width, albeit one much less than a Planck length, and thus 'makes no physical sense'.

PS  I agree with Alan's post above.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 30/10/2019 18:48:21
Quote from: Alan
It's a poor phrase, because logically it means "Bigger than you can imagine small" "Infinitesimal" is the mathematical term you are looking for.

A poor phrase, indeed. Outside its mathematical definition: “an indefinitely small quantity; a value approaching zero”, I would suggest it has no real meaning.

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Apparently! Surely everyone else can distinguish between the local absence of stuff that could be present at a point, and the universal non-presence of stuff that couldn't.

That is one of many examples of a response that is fine, in itself, but in which the essential issue definitely lacks a non-zero presence. 
As usual, I’m rushing responses in odd moments, but I will try to clarify the “issue”.  Need to look at some more posts first though.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 30/10/2019 19:04:20
Quote from: Alan
Lacking a nonzero dimension means having zero spatial (or spatiotemporal, or indeed any of the 256 dimensions that pay the rent for string theorists) extent in any direction. What it doesn't mean is "having zero dimensionality", because a point is defined by the confluence of vectors.

Thanks Alan. Just another example of my poor choice of terms; arising, no doubt, from my “hitch-hiker” status.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 30/10/2019 20:08:22
Let's go with a proof then.

P1 X is a fundamental particle
P2 X occupies volume (or space in at least one dimension)
C1 The material of X on one side is spatially separated from the material of X on the other side.
C2 X is comprised of the two chunks of material on one side and the other (X is made of parts)
C3 X is not fundamental.

P1 and C3 are contradictory, thus at least one of the premises is false.

Let's go with another 'proof'.

If a fundamental particle had some sort of nonzero width, it would have angular inertia and thus angular momentum.  While a proton (not fundamental) has this sort of 'orbital' angular momentum, nothing fundamental does. It has 'spin', but that is just a name give to a quantum property of how the particle behaves in a magnetic field.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 31/10/2019 12:12:34
Wiki says: “elementary particles still possess a spin angular momentum”; so there is probably much to discuss, but, although interesting, I think it is a subject for another thread.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 31/10/2019 12:58:43
elementary particles still possess a spin angular momentum
This is the quote in context, in angular momentum page:
Quote from: wiki
it turns out that the notion of a quantum particle literally "spinning" about an axis does not exist. Nevertheless, elementary particles still possess a spin angular momentum, but this angular momentum does not correspond to spinning motion in the ordinary sense.

Morton Tavel, a professor of physics at Vassar College, quoted in a sci-American article
Quote from: Tavel
When certain elementary particles move through a magnetic field, they are deflected in a manner that suggests they have the properties of little magnets. In the classical world, a charged, spinning object has magnetic properties that are very much like those exhibited by these elementary particles. Physicists love analogies, so they described the elementary particles too in terms of their 'spin.'

Unfortunately, the analogy breaks down, and we have come to realize that it is misleading to conjure up an image of the electron as a small spinning object. Instead we have learned simply to accept the observed fact that the electron is deflected by magnetic fields. If one insists on the image of a spinning object, then real paradoxes arise; unlike a tossed softball, for instance, the spin of an electron never changes, and it has only two possible orientations. In addition, the very notion that electrons and protons are solid 'objects' that can 'rotate in space' is itself difficult to sustain, given what we know about the rules of quantum mechanics. The term 'spin,' however, still remains."
My bold and other style edits.
The bit about the proton seems weird, given that they are actually objects with a nonzero radius that can rotate in space.

https://www.forbes.com/sites/startswithabang/2017/04/19/why-does-the-proton-spin-physics-holds-a-surprising-answer/#83185dc2c3a5
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There are two things that contribute to angular momentum: spin, which is the intrinsic angular momentum inherent to any fundamental particle, and orbital angular momentum, which is what you get from two or more fundamental particles that make up a composite particle
What they call 'orbital angular momentum' (dotted italic references throughout this post) is actually the proton physically spinning, which it can because it, being made of spatially separated parts, is not a point particle.
The intrinsic angular momentum (underlines throughout) is the same thing the wiki article is speaking about, which electrons and everything else has. This is the quantum spin you always hear about.

The article goes on in considerable depth. A good read if you're interested. Nice illustrations.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 01/11/2019 12:24:48
Quote
This is the quote in context

That's why I said there is probably much to discuss, but find time to post is getting difficult again, so I didn't want to divert from my, not very successful, attempt to move back towards the OP.

Thanks for the links.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 12/11/2019 13:47:20
Was the BB the beginning of the Universe?  Of course, scientific veracity is not a matter of democratic “vote”, but informed opinion seems, widely, to hold that this is our best current theory.  Given that response; the next question must be: “Did anything exist before the BB?”.  A few decades ago, the answer usually found was, “nothing”.  However, two things have happened to that “nothing” over time. 

1. It has become more “somethingy”, while still being referred to as nothing.  This lets in different definitions of nothing, which then lead to confused thinking/communication.

2. It has been replaced by the idea that there would almost certainly have been something, but we don’t know what it was.  This must be the “safer” option, but still leaves the question as to the whether we can say something about this “something”, that is not simply conjecture or philosophy.

Speculations can, and do, go in various directions from here, but two questions predominate.

1.  If there was nothing before the BB, could there have been a BB?
2.  If there was something before the BB, must it be eternal/infinite?

Informed opinion is certainly not unanimous on the answer to Q1.  There are those who hold that something could “emerge” from nothing, but I have yet to find an explanation that didn’t involve treating “nothing” as “something”.  A “get-out clause” is that science works with models, and we cannot model “nothing”.  How satisfying is this?

Answers to Q2 often devolve into discussions that, at best, are peripheral to the essential issue.  A major problem seems to be that, however much the people providing the explanation insist that eternity is not a length of time, they inevitably lapse into treating it as though it were.  Infinite regression is often a major component of these lines of reasoning, and the presence of the word “infinite” leads to an apparent assumption that the “sequence” under discussion is actually infinite, i.e. it somehow extends to infinity.  This may be acceptable in principle, but has no practical counterpart. 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 12/11/2019 13:51:33
In the following 10 points, I attempt to pull together some of my own thoughts about infinity/eternity.  In no way am I suggesting that this is anything more than the ruminations of a “hitch-hiker”.

1.  Infinity is not just a very big number.  In fact, it is not a number at all.

2.  Eternity is not just a very long time.  It is not time, and has no direct relationship to time, other than in our finite reasoning, and in our need to form a mental picture of “for ever”.

3.  Something that is finite can never become infinite.  Even the assertion that a finite object could “increase for ever” is misleading, because it assumes the possibility of an infinite progression.  This is often expressed as “progressing towards infinity”, or “approaching infinity”.  One example of this is the theoretical possibility is that our Universe could expand for ever.  This may be true, but it can never reach infinity, in fact, it must always be infinitely far away; and then only if the concept of distance from infinity has any real meaning, which I doubt.

4.  Mathematical infinities are theoretical concepts that are unbounded, but not necessarily infinite.  I wouldn’t try to argue with the value of infinity, as a concept, in mathematics, but it seems there are those who do.   Max Tegmark, regards infinity as “…the ultimate untested assumption.”  He says: “All of our problems with inflation and the measure problem come immediately from our assumption of the infinite.”  This must raise the question: How can we test for infinity?  Surely such a test would require an infinite amount of information, which, in a finite Universe would be unattainable. 

5.  Cantor’s “absolute infinity” may be infinite, but this cannot be proved nor disproved.  This, taken in conjunction with points four and six, suggests that infinity/eternity is not something that is amenable to mathematics, nor can it be adequately dealt with in our finite “reality”.  I am not advocating that we should not think about infinity/eternity; on the contrary, we should think about it, but stop trying to force it into a mathematical mould. 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 12/11/2019 13:58:13
6. Unbounded entities may be subjected to mathematical processes, but attempting to do this to infinity leads to     nonsensical answers.

Consider the “infinite” sequence of rational numbers.  A sample segment, e.g. 10 – 20, can be “isolated” without having any effect on “the whole”.  You can do anything mathematically permissible with these ten numbers, without directly influencing any of the others.  You can multiply 10 by 3, which gives you 30, but to suggest that this has some effect on a conceptual 30 that “exists” elsewhere in the sequence, makes no sense. 

What are you left with if you consider that you have, somehow, removed your sample from the “infinite” succession?  It cannot be two finite halves, because finite quantities are measurable, and this would give you a measure of infinity.  A usual response is that both “halves” are infinite, and mathematically, that may be acceptable, but otherwise, there are problems.  The sequence before your sample ends at 9, so by definition, it isn’t infinite.  The other sample, if reversed, ends at 11 - same problem.  Also, you have subtracted something from infinity, which you could not do if infinity were not a number.  If you are to maintain that the sequence is infinite, any work you do on it must be done without influencing the whole; otherwise you divide infinity.  Mathematically, you can do this, because, in actuality, there is no “whole”.  The sequence of rational numbers can be considered as infinite, simply because it is, like Hilbert’s Hotel, a mental concept that can never be physically realised.  It is a tool used to count objects, and objects exist in finite quantities.  Undoubtedly, someone will argue that you can also count abstract ideas, but the chances are they will not find an example of an abstract idea that is not the product of a finite mind. 

7.  Multiplying or dividing infinity makes no practical sense because the result would have to be infinite.

We have seen how this works with the sequence of rational numbers, but how might this be applied to (absolute) infinity?

To a great extent, the same reasoning applies.  Dividing infinity must result in either two infinities, which, excluding mathematical quasi-infinities, cannot be possible.  Or, it must result in two finite halves, with the implications for measuring infinity which we saw above.

A corollary of this is that there can be no change in infinity/eternity, because this would lead to a situation in which there would be eternity before the change, and eternity after the change.  Barbour has, perhaps more than most, tried to give some “substance” to the idea of timelessness, but even he seems to let suggestions of time slip in.  Platonia is timeless, but he talks of “pathways”.  To me, pathways suggest traffic, traffic involves movement and change.  I struggled with parts of this book, so I may have missed an explanation for the role for pathways in a timeless domain. 

8.  In practice, nothing can be added to infinity, because it is already everything.

9.  There cannot be more than one (absolute?) infinity, because it must contain everything.

10.  Nothing can be taken away from infinity, because, either, the remaining quantity would still be infinite, or it would be finite; in which case it could be measured, and if added to the fraction subtracted, would give a measure of infinity.  Therefore, it makes no sense to talk of something being taken away.  Furthermore, if infinity is everything, there is nowhere for any “being” to be, “who” might do the taking.  Nor is there anywhere for the extracted quantity to go.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 12/11/2019 14:03:39
My guess is that everyone who has exercised the patience to wade through these ramblings will have, long since, spotted the glaring problem with this line of thinking, in relation to the OP.

If the cosmos is infinite/eternal, and the cosmos is the “precursor” of our Universe; how could the BB, or anything else, have happened without dividing infinity/eternity?  Must we not be left with eternity before and after the existence of the Universe?

The act of asking these questions demonstrates that eternity is being visualised as a length of time.  Only if eternity is a length of time can there be a “before” and “after”.  It is tempting to think of timeless eternity as a static “now”, but, of course, someone will point out that “now” is a time related term.  Face it – we don’t have the language.

There is a way round the problem; David Bohm did much to introduce and develop it, so it has a pedigree.  What I have been referring to as the cosmos, roughly equates to Bohm’s “Implicate Order”.  His concept of “wholeness” is a very important factor. 

The timeless/changeless nature of the cosmos means that we have to look, critically, at the idea that there could be any “parts” of eternity that would be distinguishable from any other parts.  Like Barbour’s “pathways”, there would seem to be no role for “parts” in a realm in which there was no time to facilitate the making of distinctions between them.  Differentiation is redundant.  What we perceive as differences are features of the “Explicate Order”.

Our Universe equates to the “Explicate Order”.  It has time (with a defined arrow) and change.  It has distinctions between individuals and groups.  It is elucidated by the laws of physics and is well described by mathematics.  It is our reality, and we are constrained by its exigencies.

What remains now is to integrate the two concepts; to see how the Universe relates to the cosmos.  Understanding the cosmos is where an appreciation of the impact of “Wholeness” is essential.  Simply saying that every part of the cosmos is the cosmos, in its entirety, expresses the basic idea, but is still borrowing terminology from the Explicate Order.  There are no parts.  The whole just is. 

The corollary of this is that our Universe is the cosmos.  Our reality is a deceptive “shadow” of the whole.  Our perception of time, change and separation arises as a consequence of our partial perspective, and our need to make sense of our world; the world into which evolution fitted us to survive.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 12/11/2019 15:00:47
If the cosmos is infinite/eternal, and the cosmos is the “precursor” of our Universe; how could the BB, or anything else, have happened without dividing infinity/eternity?  Must we not be left with eternity before and after the existence of the Universe?

Infinite, yes. Eternal, yes, because in the absence of stuff there is no change and without change, time is meaningless. Precursor, yes: something happened within the infinite universe to produce the observable  universe, which is  clearly a division (it has a boundary) of the entire universe. So what?

I dislike your use of "cosmos" to denote something larger than the observable part of the universe. I think the general use of the term denotes exactly the observable bit, and universe clearly means "everything". All those events and objects we call cosmic are obviously observable.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 12/11/2019 16:16:34
Was the BB the beginning of the Universe?  Of course, scientific veracity is not a matter of democratic “vote”, but informed opinion seems, widely, to hold that this is our best current theory.  Given that response; the next question must be: “Did anything exist before the BB?”.  A few decades ago, the answer usually found was, “nothing”.  However, two things have happened to that “nothing” over time. 
Sorry, but I cannot think how any of this jives with science.  The BB theory is an explanation of the evolution of the universe since the BB, but not a model of how it came to be in the first place.  So it is the beginning of time as we know it (that which is measured by seconds or by vibrations of certain atoms, neither of which exists outside the BB), but the theory does not posit the absence of anything 'on the other side', which is arguably not 'before' and certainly doesn't posit 'nothing'. I'm no expert in the theories that do concern such things, and have little opinion on them, so I'll just say that theories exist, and I'm not aware of any of them suggesting a 'nothing', although 'no thing' is appropriate since the typical 'thing' we know like an atom likely doesn't exist there. All the theories seem to fall under 2) below, and not 1) here.

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2. It has been replaced by the idea that there would almost certainly have been something, but we don’t know what it was.  This must be the “safer” option, but still leaves the question as to the whether we can say something about this “something”, that is not simply conjecture or philosophy.
Conjecture yes.  Philosophy no, since these are typically QM theories and lead to models that make predictions.
I'm more interested in the philosophical aspect, which doesn't concern the nature of what's outside our little chunk of spacetime and concerns more which how any of it comes to exist at all, and my conclusion was that the very wording (the bolded part) is biased and makes assumptions that should instead be questioned.

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There are those who hold that something could “emerge” from nothing, but I have yet to find an explanation that didn’t involve treating “nothing” as “something”.
I agree with this.
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A “get-out clause” is that science works with models, and we cannot model “nothing”.  How satisfying is this?
I've never seen a scientific model positing something from nothing. It seems contradictory. Science concerns the mechanism involved, and no viable mechanism does a 'something from nothing'. It is thus a philosophical stance, and a weak one since it defies logic for the reasons you give.
It also assumes the something is caused, which I find to be a mistake. Maybe it is, but making any assumptions at all seems dangerous. I've learned to discard as many assumptions as possible. Some are really difficult.

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Answers to Q2 often devolve into discussions that, at best, are peripheral to the essential issue.  A major problem seems to be that, however much the people providing the explanation insist that eternity is not a length of time, they inevitably lapse into treating it as though it were.  Infinite regression is often a major component of these lines of reasoning, and the presence of the word “infinite” leads to an apparent assumption that the “sequence” under discussion is actually infinite, i.e. it somehow extends to infinity.  This may be acceptable in principle, but has no practical counterpart.
Language issues aside, our universe seems infinite in some ways: There is no apparent boundary to spacetime except the big bang itself, and possibly the big rip on the other side. Doesn't mean it isn't bounded, but the boundary isn't apparent. So it could work either way. I don't think it matters. The existence (as opposed to its nonexistence) of either a finite nor an infinite structure can be explained. It being finite or not seems to play no role in this essential issue.

3.  Something that is finite can never become infinite.
Trying to find exceptions to this. How about this?:
The acceleration required of my ship to escape yonder black hole is finite and increases as the ship approaches it. At the event horizon, that required acceleration (G force) becomes infinite. It's an admittedly abstract thing. The ship isn't capable of that, so it's going to fall in.
Two lines in a plane intersect in a finite distance, but as you rotate one of them, that intersection point becomes infinitely far away.  Not a point infinitely far away, but rather the lack of such a point regardless of distance.  Again, an abstract thing, not physical.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 12/11/2019 16:39:45
Only if eternity is a length of time can there be a “before” and “after”. 
I disagree. Things change. Rabbits breed, nuclei decay. This defines before and after. Nothing to do with eternity.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 12/11/2019 18:46:54
Quote from: Alan
I dislike your use of "cosmos" to denote something larger than the observable part of the universe.

I’ve explained before why I tend to follow Gribbin’s terminology, I certainly do not expect others to follow.  Should I assume that you would replace “cosmos” and “Universe” with “infinite universe” and “observable  universe”? 

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Infinite, yes. Eternal, yes, because in the absence of stuff there is no change and without change, time is meaningless.


I think that is largely in agreement with what I am saying. 

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Precursor, yes: something happened within the infinite universe

In the “infinite universe” in which there is no change and no time; “something happened” ??  You've left me way behind, there.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 12/11/2019 18:54:02
Quote from: Halc
Sorry, but I cannot think how any of this jives with science.  The BB theory is an explanation of the evolution of the universe since the BB, but not a model of how it came to be in the first place.

If that is your understanding of the quote from me; all I can say is that we speak different languages.  Your introduction of “dancing”, if intentional, is a colourful usage. :)

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these are typically QM theories

You seem to be saying that QM theories are applicable to the “something” posited as a precursor to the Universe.  Could that be right?

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I've never seen a scientific model positing something from nothing. It seems contradictory.

Sometimes I wonder if we are saying the same thing, in different languages.

Quote from: Bill
   A major problem seems to be that, however much the people providing the explanation insist that eternity is not a length of time, they inevitably lapse into treating it as though it were.

Your response seem to reinforce this.  Was that intentional?

Quote from:  bill
3.  Something that is finite can never become infinite.

So in neither of the “exceptions” you give is actually an exception, but then, I think you acknowledge that; so was there a point that I've missed?
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 12/11/2019 19:10:15
Quote from: Bill
Only if eternity is a length of time can there be a “before” and “after”.

Perhaps I should have said “Only if eternity is a length of time can there be a “before” and “after” associated with eternity. 

However, if you put that quote back in context, I think you may find that your “Rabbits breed, nuclei decay…” is not really a helpful response.


Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 12/11/2019 20:08:51
Quote from: Halc
Sorry, but I cannot think how any of this jives with science.  The BB theory is an explanation of the evolution of the universe since the BB, but not a model of how it came to be in the first place.
If that is your understanding of the quote from me; all I can say is that we speak different languages.  Your introduction of “dancing”, if intentional, is a colourful usage. :)
Jibes then.  Typo, sorry.
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these are typically QM theories
You seem to be saying that QM theories are applicable to the “something” posited as a precursor to the Universe.  Could that be right?
As a precursor to and cause of the big bang, yes.  I don't pretend to understand it all. Look at some of Sean Carroll's publications. He's on top of that sort of stuff. I'm only mildly interested since I don't really care what caused the big bang. That event didn't do anything silly like 'cause existence', except it sort of did since it caused the only sort of existence that makes sense to me.
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Quote from: Bill
   A major problem seems to be that, however much the people providing the explanation insist that eternity is not a length of time, they inevitably lapse into treating it as though it were.
Your response seem to reinforce this.  Was that intentional?
I personally don't use the word 'eternity' to mean anything except a length of time. But I do use the word 'eternal' to mean 'not contained by time'.
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So in neither of the “exceptions” you give is actually an exception, but then, I think you acknowledge that; so was there a point that I've missed?
Nope. Just a habit to look for exceptions whenever somebody makes a statement with 'always' or 'never' in it somewhere.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 12/11/2019 23:16:06
The relation of eternity to time mirrors that of infinity to number. It has nothing to do with before and after, any more than infinity has anything to do with larger and smaller. We are at a point in an eternal, infinite universe, and there are more rabbits today than yesterday. But even if the universe  is of finite duration and extent, the observation remans true, so we have a definition of "after" (and "more"). It just happens that there  are more subtle and convenient ways of measuring the passage of time than counting rabbits.

If quantum mechanics turns out not to describe what preceded the big bang, it's no big deal. We'll just have to find some other means of describing it, and preferably one that reduces to QM if t > 0. Physical laws are descriptive, not prescriptive.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 13/11/2019 18:16:49
Quote from: Alan
It has nothing to do with before and after.................. We are at a point in an eternal, infinite universe,

If we are at a point, does that not imply that there is a before and after relative to that point?

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Physical laws are descriptive, not prescriptive.

If I have ever given the impression that I did not agree with this, it was certainly not intentional.
If you were referring: “….   It is elucidated by the laws of physics”, I am at a loss to see how that could be interpreted as saying that the laws of physics are prescriptive.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 13/11/2019 18:41:28
Quote from: Halc
I personally don't use the word 'eternity' to mean anything except a length of time.

It’s good to have clarity.  IMO, holding an idiosyncratic viewpoint is better than insisting that eternity is not a length of time, then treating it as though it were just that. 

If your interpretation of eternity is that it is a length of time, and mine is that it is not, we will, probably, never make a great deal of progress, though.

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Jibes then.  Typo, sorry.

Shame! I thought your inner poet was emerging.  Dancing with concepts; I like it.  :)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 13/11/2019 19:35:27
If we are at a point, does that not imply that there is a before and after relative to that point?
Sure does! My diary has lots of scribbles for yesterday and a few ideas for tomorrow. Not to mention the rabbits!
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 13/11/2019 19:48:55
In the “infinite universe” in which there is no change and no time; “something happened” ??  You've left me way behind, there.
Why is there no change and no time in an infinite universe? There is an odour of Christian theology (the omnisicent god has no need for time) here, that has no place  in serious cosmology! Stuff happens, as observed. We have no reason to believe that the universe is not infinite, and indeed it is a lot easier to explain what happens in the observable universe if we presume that there is a lot more outside it. The trick is that anything that happens locally in an infinite universe may eventually be reflected by something equivalent unhappening elsewhere, thus preserving the eternal nature of the whole whilst permitting temporal change within it.   

Apologies for the nonsequential flow of my arguments - I keep coming across bits that I should have discussed when they arose, but real life keeps intruding! Not sure where I picked up the bit about the laws of physics prior to the big bang. 
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 13/11/2019 20:21:51
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Sure does! My diary has lots of scribbles for yesterday and a few ideas for tomorrow.

Unless you have an eternal diary, you have side-stepped the issue.  You were talking about the relation of eternity to time. You said it had nothing to do with before and after. Then you said: “We are at a point in an eternal, infinite universe”.  How can there be a point, with a before and after, in eternity which “.. has nothing to do with before and after”?

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Why is there no change and no time in an infinite universe?

I tried to address that in #267 - #270, without resorting to theology, which, I agree, has no place in serious cosmology. I could look for some examples, but don’t have time for that at the moment.  Your response to the question above could have some relevance.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 13/11/2019 20:47:59
If we are at a point, does that not imply that there is a before and after relative to that point?
There is (potentially) a before and after to any point in a temporal space.  On the other hand, I by no means consider myself to be at only one such point. I'm at quite a number of them, none particularly special.
Quote from: Halc
I personally don't use the word 'eternity' to mean anything except a length of time.
If your interpretation of eternity is that it is a length of time, and mine is that it is not, we will, probably, never make a great deal of progress, though.
Didn't say I would not accept a different definition. I just personally would not choose the word to mean that other thing.
In the “infinite universe” in which there is no change and no time;
That I do not agree with.  Infinite or not, there is very much change. At time 1 the candle is taller than at time 2, and then there's the rabbits. The count of rabbits is different at one time than at a subsequent one, and that means there is change.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 13/11/2019 23:44:37
How can there be a point, with a before and after, in eternity which “.. has nothing to do with before and after”?

OK, I wasn't being sufficiently pedantic. Eternity being an infinite line on the time axis, the position of a point on that line has no effect on the line itself. However many points we place on the line, it still stretches infinitely in either direction  from any point. The existence of 1, 7, and -3 has no effect on the number of possible integers which remains infinite, but their order describes a unique path within the integer line. As my father used to say, "the graveyards are full of men who were once indispensable". Sic transit gloria mundi!
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 14/11/2019 00:05:10
Mathematical infinities are theoretical concepts that are unbounded, but not necessarily infinite.
AAAAGH! You will be telling us next that a dog is an animal but not necessarily a dog!
Mathematics tells us that there are different infinities. All are infinite but some are bigger than others. Back to the simple case:
The sequence of integers is infinite: for any integer N, I can conceive of N + 1, so there is no upper limit to the integer series.
The sequence 1, 1½, 2, 2½, 3...... obviously (a) is infinite and (b) has twice as many members as the sequence of integers
And so forth.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 14/11/2019 01:11:20
The sequence 1, 1½, 2, 2½, 3...... obviously (a) is infinite and (b) has twice as many members as the sequence of integers
If there is a value for 'how many members', then it isn't infinite.  If there isn't, you can't meaningfully speak of doubling it.  There exists a bijunction between the integers and the latter sequence you give, thus there are no more meinmbers one sequence than the other.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 14/11/2019 10:10:35
That's the joy of infinities, and the reason Cantor lost his marbles. You can't put a limit on either sequence but the second obviously contains more elements in a given segment. It is, if you like, a "denser" infinity.

Now if I specify a sequence that begins with 1 and has no finite second element, I have defined an infinity with infinitesimal density, and if I talk about a continuum with no boundary, I have defined an infinitely dense infinity. You can have as many infinities in between as you wish. The boundary between arithmetic and algebra is that you can't handle a continuum with arithmetic tools, which places a limit on Cantor's approach.

So much for mathematics. As far as astrophysics is concerned, we seem to be living in a fairly sparse infinity with a few aggregated lumps.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 14/11/2019 12:37:29
Quote from: Alan
AAAAGH! You will be telling us next that a dog is an animal but not necessarily a dog!

That depends on how you define "dog".
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Colin2B on 14/11/2019 13:33:47
Quote from: Alan
AAAAGH! You will be telling us next that a dog is an animal but not necessarily a dog!

That depends on how you define "dog".
In the statement you are referencing I don’t believe it is dependent.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 14/11/2019 13:50:50
Alan was making a prediction as to what I would  “be telling us next”.  I reserve the right to decide what my next assertion might depend on.  :)
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 14/11/2019 13:57:06
Quote from: Halc
There is (potentially) a before and after to any point in a temporal space

Of course there is.  I thought we were talking about eternity. Only if you define eternity as a length of time could there be a point with a before and after. 

It might be worth another look at #268 – 269; especially point 7.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 14/11/2019 16:20:56
I thought we were talking about eternity. Only if you define eternity as a length of time could there be a point with a before and after.

It might be worth another look at #268 – 269; especially point 7.
Very well, we seem to be discussing a definition of eternity that isn't a length of time.  Let's see what your posts have to say about it.
From 268:
2.  Eternity is not just a very long time.  It is not time, and has no direct relationship to time, other than in our finite reasoning, and in our need to form a mental picture of “for ever”.
OK, this just reiterates what it isn't: a length of time.

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5.  ...  I am not advocating that we should not think about infinity/eternity; ...
This is the only other mention, and you seem to imply the word means the same thing as 'infinity'.  OK, perhaps that's why all the posts about infinity, despite it seeming to be irrelevant to the question I thought I was being asked.

From 269, which has only one mention of eternity:
7. Multiplying or dividing infinity makes no practical sense because the result would have to be infinite.
...
A corollary of this is that there can be no change in infinity/eternity, because this would lead to a situation in which there would be eternity before the change, and eternity after the change.
Again, you seem to just use it as a synonym for 'infinity'.

So why not just use the word 'infinity' when you mean that?  The word is already there, and it seems confusing to occasionally substitute 'eternity' for it when you mean the same thing.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 14/11/2019 17:30:33
It seems that Alan is not the only one who is not “being sufficiently pedantic”.

I do try to cover the possible alternative interpretations that my fellow not-pickers might identify, but that doesn’t always work.

Quote from: Halc
So why not just use the word 'infinity' when you mean that?

Because colloquially there is a distinction which, seemingly, I am not alone in recognising.

Quote from: Alan
The relation of eternity to time mirrors that of infinity to number.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 14/11/2019 18:02:34
On the other hand, perhaps I am being over pedantic.

Quote from: Bill
2.  Eternity is not just a very long time.  It is not time, and has no direct relationship to time, other than in our finite reasoning, and in our need to form a mental picture of “for ever”.

Quote from: Halc
OK, this just reiterates what it isn't: a length of time.
 

Let’s find the reiteration. 

“Eternity is not just a very long time”.  This says specifically that eternity is not the incredibly long time that it is often presented as.

Someone might suggest that it is, nevertheless, time in some guise.  “It is not time”, eliminates this option.

“…and has no direct relationship to time,”  This anticipates another possible “diversion”.

“…other than in our finite reasoning, and in our need to form a mental picture of “for ever”.  This acknowledges the underlying need for a term that links infinity to time in our 3+1D world.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Halc on 15/11/2019 01:04:59
Quote from: Halc
So why not just use the word 'infinity' when you mean that?
Because colloquially there is a distinction which, seemingly, I am not alone in recognising.
You didn't seem to give a distinction. You pointed to two posts both of which only used the word as 'infinity/eternity', indicating you mean the same thing by the words, not distinct concepts.

Quote from: Halc
OK, this just reiterates what it isn't: a length of time.
  Let’s find the reiteration.
I mean you've said it more than once.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 15/11/2019 01:37:58
"What I tell you three times is true."  Lewis Carroll
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Colin2B on 15/11/2019 09:19:12
"What I tell you three times is true."  Lewis Carroll
Yes, but The Bellman believed in Snarks.
Most of this thread seems to be about building Snarks, not much real physics.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 15/11/2019 09:59:08
And all the time, the Snark was a Boojum.
Which I pointed out earlier.
Though in a parallel universe.

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"The time has come," the Walrus said, "To talk of many things: Of shoes--and ships--and sealing-wax-- Of cabbages--and kings-- And why the sea is boiling hot-- And whether pigs have wings."
which pretty well sums up this forum! Vivat!
Title: Re: Was the Big Bang the beginning of the universe?
Post by: RobC on 15/11/2019 10:15:12
Here's the answer --
https://www.quora.com/What-banged-at-The-Big-Bang
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 15/11/2019 18:43:31
Great link, Rob.  Let’s not nit-pick the story; it has a lot going for it.

This is worth a look, as well.
https://www.quora.com/What-existed-before-the-Big-Bang-1

 
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Keep in mind, Nothingness does not exist in our universe, only in the Cosmos. Another way to define Nothingness is that it is an absence of Somethingness.

There’s enough in that quote, alone, to keep this thread going for another 300 posts, but it’s probably time to wind it up, before we are all so to speak, "snarked".

Time to consider some other laws.

Deutsch's Law
Every problem that is interesting is also soluble.

Quote from: Alan
So what?

Have we spent over 300 posts looking for a nonexistent solution?

Take heart, though:

Smolin's Second Law
In every period and every community there is something that everybody believes, but cannot justify. If you want to understand anything, you have to start by ignoring what everyone believes, and thinking for yourself.  (My bold).

If all else fails:

Davies' Second Law
Never let observation stand in the way of a good theory.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Colin2B on 16/11/2019 04:05:36
it’s probably time to wind it up, before we are all so to speak, "snarked".
I think you have already snarked yourself Bill  ;)

Quote from: Alan
So what?
Have we spent over 300 posts looking for a nonexistent solution?
No, just looking in the wrong place.
Physics isn’t really discoverable by this type of ‘analysis’, in fact it has often taken science down the wrong road for a long time eg Aristotle for almost 2000 years. Alan Guth, for example, has a very different approach through investigation of the behaviour of subatomic particles in extreme conditions and some specific problems, eg magnetic monopoles, which lead to a very radical approach to understanding the development of the early universe. Some of his ideas may seem strange to our classical minds - the universe appearing out of nothing, our timeline not being eternal (eternity = infinite time) - but they are grounded in some pretty solid physics. Not saying he is completely right, but at least it’s physics.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: alancalverd on 16/11/2019 10:27:58
Have we spent over 300 posts looking for a nonexistent solution?
Obviously not. If there was a big bang, either nothing ever changed before it, in which case t< 0 is meaningless, or something did, in which case there is a solution which we have yet to find.

What I think we almost established is a common vocabulary that admits the possibility of the universe being infinite and the observable universe being a phenomenon within it. That is a sufficient framework for searching for solutions, the acid test of which is that they must yield the status quo for t > 0.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 17/11/2019 13:12:36
Quote from: Colin
I think you have already snarked yourself Bill  ;)

It's a congenital condition, Colin.  Too late to do anything about it now; even if I wanted to.
Title: Re: Was the Big Bang the beginning of the universe?
Post by: Bill S on 17/11/2019 13:22:57
Quote from: Alan
What I think we almost established is a common vocabulary that admits the possibility of the universe being infinite and the observable universe being a phenomenon within it.

That, in itself, is quite an achievement. 

Pete summed it up, years ago, #20:

https://www.thenakedscientists.com/forum/index.php?topic=53002.msg445072#msg445072

Quote from: Bill
1.  Is infinity a number?

Quote from: Pete
No. It's not a number. It's a concept/idea.


Quote from: Bill
2.  Is eternity a length of time?

Quote from: Pete
No. Just like eternity [infinity?] it's a concept. Think of it as infinite amount of time.

Mathematical infinities provide us with all we need to explore the physics of our Universe.  Maths and physics can even provide theories for how our Universe can be here.  What more could we need? Nothing.  What more might we want? Could be, that depends on how closely we want to look at infinity,  and how “snarked” we are.