21

Physics, Astronomy & Cosmology / Re: Why Can Photons And Other Subatomic Particles Be In Two Places At Once ?

« on: 28/07/2020 13:17:44 »

A realist (counterfactual) interpretation (like Bohm) would say that the particle (photon, electron, cat) at a given time is in fact at single location X and state S and since there's been no measurement, that location and state is simply unknown to the observer.

Only with respect to the "Explicate Order".   

22

Physics, Astronomy & Cosmology / Re: How Did Time Come Into Existence ?

« on: 26/07/2020 19:59:14 »

'Happened' is a verb tense that simply suggests that it occurred prior to some reference event,

That doesn’t remove the “action” from the verb.  “it occurred” suggests that there was an element of change involved, rather than stating that it was an eternally “existing”, unchanging entity. 

So how could the BB have preceded this post? 

I don’t understand the question.  I would certainly not suggest that this was posted prior to the BB. 

How can the big bang happen?  Things 'happen' in the course of the flow of time, so it implies such a flow, and thus is a problem I suppose for those that suggest such a flow.

We’ve visited “tensed” and “tensless” time before.  There’s a fairly recent one at:

https://www.thenakedscientists.com/forum/index.php?topic=73398.msg545390#msg545390

Neither removes the problems that are relevant to the OP

Coming of anything into existence requires time, so it is contradictory for time to come into existence. It exists or it doesn't, but 'coming into existence' is 'becoming', which is a process, and process requires time

Perhaps there are some things we should accept that we agree on, so we can clear them out of the way before, possibly, addressing the “basics”?

Lots more things to consider in this thread, but duty calls.

23

Physics, Astronomy & Cosmology / Re: How Did Time Come Into Existence ?

« on: 26/07/2020 17:33:07 »

Alan, there are points to which I hope to return, but in the meantime, could you say something enlightening about "unreal" particles with negative mass, please?

24

Physics, Astronomy & Cosmology / Re: How Did Time Come Into Existence ?

« on: 26/07/2020 15:10:00 »

Time is what separates sequential events. If there are no sequential events, the concept of time is meaningless.

Cows occupy fields. If cows did not exist the concept of real cows would be meaningless, but fields would not cease to exist.

Your analogy would work well if cows were defined as being causally related to the existence of fields.

Lets go back to the OP.  “How did time come into existence?” 

If I answered that by saying: “It couldn’t have come into existence, because that would necessitate change, and therefore, time by which the sequential (before and after) events could be separated”; would that be non-scientific?

25

Physics, Astronomy & Cosmology / Re: How Did Time Come Into Existence ?

« on: 26/07/2020 14:47:17 »

Philosophy covers much more than just that one topic.

Perhaps you are assuming I said something I didn't.  In any event, this would take us way off topic..

Our origin isn't the problem.  Cloud cools. Planet condenses out of that. Life forms. Poof: our origin explained.

All these things require time.  Correct me if I’m wrong, but I think the OP asked how time came into existence.

Possibly my use of the words “our origin” caused confusion.  In the context of the OP, I rashly assumed that this would be interpreted as the origin of the Universe, or the cosmos, or whatever title one might wish to attach to a point to which the OP’s question might be relevant.

I always wondered about what it meant for space to expand 2x each tiny fraction of a second. How is a second meaningful at that stage? There's no light, matter, or any regular process by which time can be meaningful. But maybe that's just me being ignorant.

I would hesitate to impute ignorance to someone of your manifest capabilities. 

If space is expanding, then either space = nothing; which makes no sense; or something is changing, which requires time.  Seconds are what we choose to call specific divisions of time, so a second must be meaningful.

26

Physics, Astronomy & Cosmology / Re: How Did Time Come Into Existence ?

« on: 26/07/2020 14:15:57 »

Time is what separates sequential events. If there are no sequential events, the concept of time is meaningless.

Agreed.  Would you consider it correct to interpret this as implying that time has no independent existence?

If there were no events before the BB, time did not pre-exist the events that occurred thereafter.

This leaves a major question unanswered.  If there were no events and on time before the BB, how could the BB have happened?

27

Physics, Astronomy & Cosmology / Re: How Did Time Come Into Existence ?

« on: 25/07/2020 21:23:45 »

https://www.thenakedscientists.com/forum/index.php?topic=72126.msg530896#msg530896

"Mefinks" we've been here before.

28

Physics, Astronomy & Cosmology / Re: How Did Time Come Into Existence ?

« on: 25/07/2020 21:15:37 »

This is a philosophical topic and probably belongs in Just-Chat rather than physics.

Can’t agree with that.  Philosophy might attempt to explain why we are here.  (good luck with that). 
This addresses the question as to how we can be here. Wouldn’t that be fundamental to scientific thought?

As far as I know, it isn't wrong to discuss time on the other side of the big bang event,

In fact, if time cannot be created, it becomes a necessity, if one wants to question our origin.

… since it is not necessarily ordered there, the word 'before' or the tense 'would have had to' may not be applicable.

For time to have been created, to come into existence, there would have to be a time when there wasn't time, which is self-contradictory

So, something, including time (?) must always have “existed”, and is, therefore, eternal.  In which case, 'before' and 'would have had to' cannot be applicable, unless eternity is a length of time.  That’s where it gets interesting.

29

Physics, Astronomy & Cosmology / Re: Is there a metric for complexity?

« on: 23/07/2020 21:37:13 »

Bigger whorls have little whorls
That feed on their velocity
Little whorls have lesser whorls
And so on to viscosity

Like it!     

But once it cools and sets so thick
It waxes really sticky,
Internal friction plays its part.
Escape can be quite tricky.

30

Physics, Astronomy & Cosmology / Re: Why is ‘NOW’ Not The Same Everywhere ?

« on: 23/07/2020 21:12:55 »

If Minkowski was right, it must be meaningless to talk of “now”.  We have to consider “here and now” as a spacetime event. 
If you add to that “No man liveth more than that infinitesimal point of time that is the present”.  Marcus Aurelius. 
You have the sort of thing that Halc is saying.  Wherever I go, I’m always here now.                                                                                                         

31

Physics, Astronomy & Cosmology / Re: How do we know the Universe is expanding, and expanding into nothing?

« on: 21/07/2020 14:59:42 »

……expanding into nothing.

If nothing doesn’t exist, how can anything expand into it?  Nit-pickers could have a great time finding a different way to express that idea, though.

32

Physics, Astronomy & Cosmology / Re: Do our thoughts have mass?

« on: 20/07/2020 17:09:43 »

https://www.goodreads.com/work/quotes/197917-thought-as-a-system

Could be some relevant thoughts here.

33

Physiology & Medicine / Re: Can exercise make your hair go grey?

« on: 20/07/2020 17:02:46 »

Hi  HunhisWillia, welcome.

"I used to think I'd like less grey hair. Now I'd like more of it."  Richie Benaud.

By the time you get to my age, you are more interested in preserving what might still be underneath the hair, whatever its (lack of) colour.

34

Geology, Palaeontology & Archaeology / Re: How common are crystalized steinkerns

« on: 19/07/2020 13:07:58 »

http://www.discoveringfossils.co.uk/walton-on-the-naze-essex/

Back in the 70s & 80s, when we didn’t have to wear silly hats, I used to take groups here.  Casts were not common, due to the sandy nature of the deposit; but at some levels, clay and iron concentrations change this situation. 

35

Physics, Astronomy & Cosmology / Re: How do we know the Universe is expanding, and expanding into nothing?

« on: 15/07/2020 11:47:29 »

Exactly! 

The analogy works only if you don’t try to look as far as the crust.  Interesting to compare this with Hilbert’s Hotel and all the examples of infinite sequences.

36

Physics, Astronomy & Cosmology / Re: How do we know the Universe is expanding, and expanding into nothing?

« on: 14/07/2020 16:08:01 »

There was space which doesn't contain bread before the experiment, but does contain bread afterward.

True; but the space was not empty before the bread arrived.  What did the bread displace?

37

General Science / Is this the future?

« on: 13/07/2020 19:01:03 »

https://www.laboratoryequipment.com/566170-Robot-Scientist-Quickly-Discovers-New-Catalyst/ 

Robot Scientist Quickly Discovers New Catalyst

This is not just another machine in the lab: it’s a new superpowered team member

And no sexual/racial prejudice.  Oh wait; it might be programmed in.

38

Physics, Astronomy & Cosmology / Re: How do we know the Universe is expanding, and expanding into nothing?

« on: 13/07/2020 15:56:55 »

But still, it expands to space around it which was previously empty.

Only if you accept that empty space really exists.

39

General Science / Re: How does entropy and the second law of thermodynamics work??

« on: 11/07/2020 20:32:15 »

A few minutes available to add a bit to Carroll's quote.

     He appears to say that entropy can, and perhaps should, evolve in either direction, with equal probability.  So why does entropy increase?  The simple answer is because there are vastly more potentially high entropy states than low entropy states towards which evolution can occur.  Therefore, there is a much greater chance that any low entropy state will evolve into a higher entropy state.  It's just statistics, what could (physically) happen is not observed, because the age of the Universe is not long enough for its occurrence to be remotely likely.

40

General Science / Re: How does entropy and the second law of thermodynamics work??

« on: 11/07/2020 13:24:12 »

Hi π5209806, welcome to TNS.

The Start of Time?

The second law of thermodynamics dictates that in a closed system, entropy tends to increase, or to remain constant.  In spite of the presence of the word “tends”; the assertion “it never decreases” can still be found attached to many explanations.  Clearly, this should give us pause for thought.

Unfortunately, I’ve misplaced the source of the quote “entropy tends to increase”, and don’t have time to search for it now.  However, as stressed elsewhere, the law relating to the increase of entropy in a closed system is a statistical law.  A spontaneous decrease is not physically impossible, it’s unlikely, in the extreme.

Sean Carroll points out that:

    “The chances of any low entropy state evolving into a high entropy state is the same as that of any high entropy state evolving into a low entropy state.”