[Zavenoa]

Is there anywhere in the current universe we know of that reaches a billion kelvin?  Couldn't that have something to do with it?  The hottest white dwarf is around 200,000 kelvin, 1/5, but what about larger stars.  I concede I do not know enough about the relative heat when comparing star size, I would think the bigger they are the hotter they get, but could not find data for anything other than white dwarfs.

As far as the size of the Universe at 10^-32 seconds, they can't substantiate anything, yet.  From what I've read, only at 10^-11 seconds do things become "less" speculative, whatever that means.

Parallel Universes aside, there is also the theory that the Universe was never created, but instead has been continually bouncing back and forth from a period of great expansion back to the big crunch.  What we think of as the big bang, was simply the universe starting a new period of expansion after a big crunch.  This could make sense in a way if near the end of each big crunch vast amounts of mass is converted into energy at a single time causing, well, a very big bang.  As long as the amount of mass and energy in the universe remains the same, regardless of whether there is more energy or mass at a given time, this theory would appear to work because the mass that was converted into energy to cause the big bang could then be turned back into mass in some manner.  But as you stated, why didn't it just collapse into a black hole?

I would have to say the biggest issue I have is wrapping my head around anything infinite, whether were talking about an infinite empty universe past the point the universe has currently expanded to or time as infinite with continual expansions and collapses of the universe.  Infinity in any context may be too much for my feeble human mind to comprehend.

My gut tells me that as we learn more about the behavior of the quantum world and the closer we get to understanding how it truly effects the macro world (equation of everything), the closer we will come to understanding the really tough questions, like how something can come from nothing.

[yor_on]

What astronomy and physics has done is to extrapolate from astronomical evidence, as luminosity and stars spectra. And so far it seems to fit, with how stars come to be the first generation, to the generation of star the sun is, as well as a inflation and expansion. It's like a very complicated puzzle where you use all you know, and can find out, to put the pieces together.

"The only elements that would have been formed from the big bang are hydrogen, helium, and perhaps trace amounts of lithium. Elements up to iron can be produced in a star by nuclear fusion. (Heavier elements require more energy to start the fusion than is released in the fusion reaction--i.e. energy is LOST. Therefore, only elements up to iron are formed by nuclear fusion.) In a star like our sun, there is not enough mass to create the pressure and heat needed for even the fusion into iron. Our sun will produce metals only up to carbon and oxygen.

Any metals heaver than iron could only be produced in a supernova. (Just a note, astronomers and astrophysics use the term "metal" to mean any element heaver than hydrogen or helium).

The fact that our sun contains trace amounts of iron and heavier metals means it must have been there when it formed, since these cannot be formed by the nuclear fusion within our sun. Since first generation stars would only contain hydrogen, helium, and trace amounts of lithium from the big bang, our sun is not a first generation.

This makes sense since our sun is only around 5 billion years old and the universe is about 16 billion (opinion varies from 11 to 20 billion, but 16 is right in there and generally accepted). That leaves at least 10 billion year for things to have happen before our sun formed: That is a lot of years for other stars to have formed and died, recycling some of its mass back into the universe and our sun. Since the life cycle of very large stars could be as little as 100 million years to supernova stage, the sun could conceivably be many generations along."

At the beginning you used earths relative motion to see how stars, apparently, 'moved' with earths position relative the sun, called parallax, to define a distance. To define those you first have to know the distance from Earth to the Sun, called one astronomical unit (one AU). then you use trigonometry to find a distance to the closest stars. As soon as we could send up probes in space we started to use them too to get those distances better defined, as you won't have a atmosphere distorting in space.

"Some of the best data on stellar positions in the sky come from Hipparcos, a spacecraft launched in 1989 by the European Space Agency. Hipparcos has measured the trigonometric parallaxes of about 10,000 stars to an accuracy of better than 10 percent, out to a distance of about 300 light-years. But our galaxy is about 100,000 light-years across, so parallax measurements become useless long before we approach the distances to other galaxies." from How do astronomers measure the distances...

To get further out, we make some assumptions, as you can read in that article too. The assumptions are about Cepheid stars being stable objects, presenting themselves astronomically the same way no matter the distance.

"Early in this century Henrietta Swan Leavitt discovered that the longer the period of variation of a Cepheid variable, the greater its luminosity. Another American astronomer, Harlow Shapley, then was able to correlate the brightnesses of Cepheids with those of known types of ordinary stars, tying Leavitt's relative distance scale to an absolute one. "

Here is more about determining astronomical distances. Determining Distances to Astronomical Objects by Björn Feuerbacher.

Einstein wanted a static balanced universe and got rather upset when Fridman showed that there were other possibilities 1922. The Theory of the expanding universe as originated by A. A. Fridman.

Fridman was a Russian mathematician who worked it out from Einsteins equations. Some years after his, too early death, another guy Lemaitre, a French cosmologist this time, came and developed a independent theory which went further than Fridman's three models. I think he was the guy that first presented the idea of a universe starting in a very compact area, to then 'explode' outwards. He studied mathematics under Eddington, and a brilliant mathematician. And one has to remember that it all fits so far, the whole idea of creating 'star dust' from light (energy), becoming first generation stars, becoming later generations, to the way we measure distances. Whatever ideas that might replace it must also fit all of this, and do it even better.

[yor_on]

"I might be coming to the wrong conclusion here, but if both mass and space can move, wouldn't that make faster than light travel possible?  For example, if I'm moving at 99.99% the speed of light and I warp the space behind me by dragging and stretching it, that would increase the distance I've traveled meaning I actually traveled faster than light.  However, it doesn't seem you would be able to use this to move to a destination faster than light, simply further away from one."

You have a Lorentz contraction at relativistic speeds, acting in the direction you travel. That one can be seen as traveling ftl, ignoring that lights speed in a vacuum won't change for you, so your rocket do 'warp' the space in front of you. But it is complementary to the time dilation your origin find you to have. According to their measurements it's your clock that have slowed down instead. None of those definitions are wrong though, both come from measuring, using ones local clock and ruler.

[yor_on]

I think this is the current definition.  Inflation.

[Pr. snoerkel]

yor_ons post seems to imply that I am trying to promote some kind of a steady state Universe.
Not so. I just wonder what will be the end of an ever increaing Universe. According to theory, the proton is unstable with a half time of 10E36 years. In case of proton deficit, neutrons will decay to protons. So, eventually, space will be totally without matter, enthropy will reach maximum and time will stop. The Universe will be very large then - or will it? How would one meassure distance without matter and without time?

[Zavenoa]

Might time itself not be a construct of observation?  I don't want to divert into the quantum world here, because I don't know/understand enough about it, but the basic principle I do understand is that by observing something, reality is changed (see observer effect).  If there is no matter, there will be nothing to observe the universe (that we know of).  I don't think the observer effect is restricted to life or intelligence, but I do not know.

A thermodynamic equilibrium certainly suggests that time, even if continuing, would have nothing to observe it and no reference point to base how much time has elapsed.  If you cannot measure it, does it exist?

Edit: Sorry, that doesn't answer your question, but simply restates it in a different way.

[yor_on]

Not so Pr

You wrote "the present one seems a little odd. First the Universe was created out of nothing or by collision of branes or something. Then it expanded faster than light. Finally it did not collapse into a black hole when matter was created, as it should have done according to the laws of gravity."

The last link makes a very readable presentation of inflation, and the Big Bang, as well as 'new ideas' in physics as a whole. And I have a feeling that some readers might want it too, to compare ideas. As for why matter inside this universe didn't collapse into some black hole, I guess I would refer that to the 'inflation' being ftl myself? The dust 'coagulating' into first generation suns. When it comes to Einstein the writer isn't as acknowledging as I would prefer though Although all physics build on others works, I still think Einstein did some pretty remarkable thinking. Not only SR and GR, but being one of those defining entanglements, laying a primary ground for quantum mechanics, in his work on Brownian motion, and the photoelectric effect.

http://www.aip.org/history/einstein/essay-brownian.htm
http://www.aip.org/history/einstein/essay-photoelectric.htm

[yor_on]

Then again, I'm not sure about that that the inflation in itself is applicable as a explanation, even if I assume it to be isotropic and homogeneous, meaning that it had a perfectly even (uniform) spread of 'dust', the same concentration everywhere. Maybe the universe 'rotates'? Maybe that would have something to do with it? Or maybe we should stop looking at it as a 'common universe' which then would be my hobby horse.

[Pr. snoerkel]

Zavenoa proposes that time itself could be a construct of observationm and I agree, at least to the point that in our perception time and space are two quite different things, although we for a century have known that space is connected to time. But if time stops when the enthropy reaches maximum, distance looses its meaning as well. So, my proposal is that in tha absence of matter, there will be no time and distance, meaning that only energy remains, and the Universe could be seen as both enourmeous and a singularity where all energy is located in one point.
This idea has its equivalent in the string theory, where most dimensions are reduced to nothing, only space-time has volume, and I suggest that is because of the presense of gravity in the present Universe. If gravity did not exist, as may happen in the far future, also space-time would contract.
Incidently that picture is the same as the start of the big bang that official science promotes.

[yor_on]

Oh yes, gravity is indeed the 'metric' of space. And also the thing defining it three dimensionally (in reality four dimensionally though), as I think too. Or maybe one should consider it a symbiosis? As mass (energy) is what defines that metric of gravity. A pure vacuum, without gravity, could be described as one single coherent 'frame of reference' I think, both from a time dilation and a Lorentz contraction.

[Zavenoa]

So, my proposal is that in tha absence of matter, there will be no time and distance, meaning that only energy remains, and the Universe could be seen as both enourmeous and a singularity where all energy is located in one point.

Incidently that picture is the same as the start of the big bang that official science promotes.

This would appear to support the idea that this is not the first "cycle" of the universe.  I mentioned in an earlier post the idea of an ongoing transition from inflation to deflation, but the deflation and ensuing great crush may not be necessary if this is correct.  It may be that the universe simply expands until a singularity, all laws of physics break down, and expansion begins anew with another big bang.  This may also help explain some of the issues with the big bang theory involving a different set of rules for the laws of physics.  If you begin at a singularity, and "broken" laws of physics, they may not correct themselves immediately, or at all.  This would sort of support the steady state theory, although not in the way Sir James Jeans presented it.

[Pr. snoerkel]

It seems that we are much in the same line, then. Let us try to evalve from there:
Assuming that space-time will collapse in the absence of gravity, I will then propose a slight modification of that theory. I will propose that if force of gravity is below a certain threshold value (possibly linked to the uncertainty principle), still the collapse will take place.
Now imagine the Universe in a far future. Black holes evaporated due to Hawking-radiation, most (but not all) protons decayed. Universe consists of lonely protons moving among each other. Entropy can still increase (by further proton decay), so time is running. But the distance between the protons is high, and force of gravity now at the aforementioned critical level.
Suddenly a proton decays and space-time around it, already at the critical level, immediately collapses. The photons that were contained in that particular volume of space are concentrated in a point, from where it starts radiating into the surrounding space at a very high energy level.
The local collapse affects space around it, since the surviving volume of space-time must relocate to fill out the gap left by the collapse. Space-time and the protons it contains start moving against the point of collapse at about light speed. Once moving, there is nothing to stop them until they start interacting with each other near the point of collapse. At that point nuclear reaction takes place and emitted radiation condenses to matter by the same mechanism as in the traditional big bang theory. The difference is that matter is formed over time and the concentration of mass will never reach that needed to form a black hole. The beauty of that is of course that we need not postulate a change in the laws of nature as needed in the traditional big bang theory.

[dlorde]

...  It may be that the universe simply expands until a singularity, all laws of physics break down, and expansion begins anew with another big bang.  This may also help explain some of the issues with the big bang theory involving a different set of rules for the laws of physics.

This sounds rather like Roger Penrose's Conformal Cyclic Cosmology, where, at the heat-death, time and distance become meaningless and the state of the universe becomes equivalent to a low-entropy big bang scenario... or something! see if you can make sense of it...

[Pr. snoerkel]

While I am not opposing Roger Penroses ideas, I believe a simpler explanation will do. I see those theories as a an attempt to preserve the determination principle from classical physics.

[AndroidNeox]

All of our science, logic, and philosophy is based on causality. When we project our models of the cosmos backward in time, we run into a point about 13.8 billion years ago when causality breaks down. How to explain or describe a non-causal condition eludes me and everyone whose work I've read on the problem. Generally, physicists aren't very good at these sorts of problems and assume things like the physical laws preceded spacetime and matter.

The only logically-consistent model I've been able to come up with is that the background of reality is noncausal... boundless information but no cause and effect. As evidence of this I point to "spigot algorithms" which theoretical physicists originally argued were impossible because they rely on accessing infinite information via a finite process. The theoreticians shut up when the Bailey–Borwein–Plouffe formula was proven true. I think they shouldn't have. Spigot algorithms have all the attributes of look-up algorithms rather than calculations.

Quantum mechanics provides and explanation/rule for how (but not why) a finite, causal universe would appear within that chaos. QM requires that all observations/interactions be causally-consistent. Inconsistencies would yield states (operators or eigenstates) whose matrix is non-Hermitian. Schrödinger said these were "unobservable".

It might be that there is something inherent to the structure of observation that filters out all non-causal observations.

Cosmologically, it's not hard to get from a Planck-scale universe containing exactly one quantum of "stuff" to a universe that looks like ours. The tough part is getting to something from nothing. The difficulty is providing an explanation (inherently causal) of a non-causal event.

[Pr. snoerkel]

Quatum mechanics, at least, is not based on causality, since although there might be a reason why an atom decays at that precise moment, nobody will ever know what that reason is. If you have two unstable but identical atoms in front of you, you will never be able to tell which one will decay first. Neither will anybody else.

[Pr. snoerkel]

Quantum mechanics also explains why the question "How can something be created out of nothing?" is not valid.
The uncertainty principle states that a volume of space-time will contain virtual particles, so the space will always contain something. If, in the absence of matter, space shrinks, so does time. Energy is defined as potential work per time unit so energy comes and goes with the space time.

[borwnthomas]

Hi to All! I am a new guy here and recently joined the forum to participate in interesting discussions.

[dlorde]

Hi to All! I am a new guy here and recently joined the forum to participate in interesting discussions.

Welcome!

Btw, that introduction would probably get more attention in the Guest Book thread...

[Expectant_Philosopher]

Replies like #7, encompass us in the observations of the physics of this age.  At an early age space is the distance between objects in the room.  Later we learn that space is the void between worlds.  In quantum science we learn that space can have infinitesimal dimensions, with vast distances in the subatomic realm.  In cosmology our entire universe, all 13.5 billion years of it a speck on a brane, our expression in the multiverse.  To me it seems like a series of wrappers, or skin of the onion.  You peel one back and there is just another world inside, or more appropriately here,  as we expand our minds we discover another layer surrounding ourselves expanding what we consider as real. 

For our existence a transitive state had to have occurred.   Transition implies structure, for our limited understanding of the cosmos, our existence implies the Big Bang did not come from nothing, rather from something.   X reacted with Y and 13.5 billion years later we hold this conversation.  Common imagination limits our ability to conceive another wrapper surrounds our thirteen and half billion years of our Existence.  We are so egotistical to believe that before our reality, there was no reality, that there was nothing. 

I am completely comfortable with this state of affairs.  I like the physical, it is comforting, it is a playground to experience and enjoy.  I like its complexity, and know it will keep me entertained for a number of years.  Can I drop the other shoe?  Can we know an existence outside of the physical realm?  But if you believe in an existence outside of the physical realm, aren't you expressing just another structure? For want of a clearer term, just knowing the existence of a "spiritual" realm implies not only the capability for it to be a wrapper around our existence but that it permeates our entire existence as well. 

Reply 7 gives the responder comfort to "know" the extent of reality, but for those of us who want more that can never suffice.  We see aeons of time and we want assurance that there will be space enough.