0
$\begingroup$

In the Big Bang model of the Universe, every observable thing is thought to have expanded very abruptly from a point of infinite density and zero volume. However, the problem with this assertion is that for something to expand it first needs a locality in which to do such, which brings us to my question. How can scientists believe that "everything" was condensed and then suddenly expanded, since such is automatically an oxymoron?

Expansion is a physical property of the universe and yet if "everything" had no where to expand, how could it have expanded? There was "nothing," was there not? Even if we drop the big bang model and talk about "everything's" being in a singularity point, the question still stands.

Where was the singularity point? Asked differently, into what is everything expanding (which is a rhetorical question I ask to implicate space-time as necessarily existing irrespective of any theoretical expansion and likely so vastly that one might as well assume that space-time is infinitely large).

As well, it seems counter-intuitive, as little impressive a word as that is given its context here, that something like... well, "everything" could be condensed in the first place, let alone infinitely condensed and with zero volume. When thinking about the big-bang model, I can't help but conclude that a mere analogy was originally used for stellar birth, evolution and finally explosion. The issue though is still extension.

As far as I understood it, the big bang model states that space itself was also condensed along with everything else in the observable universe to a point of singularity. So, if that's the case, then [where] was the singularity point?

It ends up becoming an infinite regress, of course. Or, if you don't like the issue of "time" presupposed by my question, then look at the question after the universe started expanding. All the matter had to expand somewhere and "somewhere" is not "nothing." - It just seems that the model is somehow overlooking said feature of the actual universe and trying to account for it by mere assertion.

If you want to call it space-time, extension, space, where everything supposedly expanded to and is and is still expanding to, then that's my question. How does the theory allege where everything is yet at the same time assert that prior to the singularity point, there was literally nothing.

$\endgroup$
  • $\begingroup$ respectable questions ... somehow a kind of theory axiom, that may evolve if the theorist encouters inconsistancies $\endgroup$ – user10314 Jan 7 '16 at 0:36
  • 3
    $\begingroup$ See astronomy.stackexchange.com/questions/13060/… - the universe has never been one single point. $\endgroup$ – HDE 226868 Jan 7 '16 at 0:48
  • 2
    $\begingroup$ Some good questions. The center of the observable universe is you. The big bang (or everywhere stretch), happened everywhere but to the observable universe, you are the center and, so am I and so is he and so is that star way way way over there. youtube.com/watch?v=q3MWRvLndzs and similar question here. physics.stackexchange.com/questions/173001/… $\endgroup$ – userLTK Jan 7 '16 at 5:09
1
$\begingroup$

In the big bang model of the Universe, every observable thing is thought to have expanded very abruptly from a point of infinite density and zero volume.

Thats not quite true. Have a look at Wikipedia where you can read this:

"Extrapolation of the expansion of the universe backwards in time using general relativity yields an infinite density and temperature at a finite time in the past.[18] This singularity signals the breakdown of general relativity and thus, all the laws of physics. How closely this can be extrapolated toward the singularity is debated—certainly no closer than the end of the Planck epoch. This singularity is sometimes called "the Big Bang",[19] but the term can also refer to the early hot, dense phase itself,[20][notes 1] which can be considered the "birth" of our universe."

You can't necessarily extrapolate back all the way to a point singularity.

However, the problem with this assertion is that for something to expand it first needs a locality in which to do such, which brings us to my question.

There's no problem with space expanding. Don't think of space as nothing, Einstein didn't, and nor do modern physicists such as Nobel prizewinner Robert B Laughlin.

How can scientists believe that "everything" was condensed and then suddenly expanded, since such is automatically an oxymoron?

Because there's good scientific evidence that the universe is expanding. And when you "wind back the clock" you find that all the galaxies were in the same place 13.8 billion years ago.

Expansion is a physical property of the universe and yet if "everything" had no where to expand, how could it have expanded? There was "nothing," was there not?

No. Space expanded, and space isn't nothing. As to what caused the big bang to occur, I don't know. Nor do I know what the universe was like 13.8 billion years ago. But I know of no infinities in nature, and I would challenge the alleged point singularity at the centre of a black hole and refer instead to the frozen star interpretation. In similar vein I would challenge the alleged point-singularity 13.8 billion years ago.

Even if we drop the big bang model and talk about "everything's" being in a singularity point, the question still stands. Where was the singularity point?

I think you shouldn't drop the big bang model, but instead you should drop the singularity.

Asked differently, into what is everything expanding?

Nothing. I know this is hard to imagine, but try to. Space is expanding, and there is no space beyond it. So there is no beyond it. As to whether this means you end up coming back round full circle or the universe is some "hall of mirrors" or something else, I don't know.

(which is a rhetorical question I ask to implicate space-time as necessarily existing irrespective of any theoretical expansion and likely so vastly that one might as well assume that space-time is infinitely large).

No, one might not. Because the universe doesn't expand for nothing. It expands because space has a kind of innate "pressure", as per the energy-pressure diagonal in the stress-energy-momentum tensor. And if the universe was infinite, the pressure would be counterbalanced at all locations. An infinite universe could not expand.

When thinking about the big-bang model, I can't help but conclude that a mere analogy was originally used

For an analogy, get a stress ball and squeeze it down in your fist. Then let go.

The issue though is still extension. As far as I understood it, the big bang model states that space itself was also condensed along with everything else in the observable universe to a point of singularity.

See what I said above. Big bang cosmology doesn't actually say everything was condensed to point singularity.

All the matter had to expand somewhere

There wasn't any matter initially. Remember the wave nature of matter, and pair production. We can quite literally make matter out of electromagnetic waves. These wave propagate through space, and are effectively wave sin space. So we make matter out of waves in space. So start with space, and do somehting to it such that it rings like a bell and is full of waves and starts expanding. As to what, I don't know.

How does the theory allege where everything is yet at the same time assert that prior to the singularity point, there was literally nothing?

It doesn't. It goes back as far as a very dense universe. The stuff you hear about a point singularity and creation ex-nihilo is popscience, not big bang cosmology.

$\endgroup$
  • $\begingroup$ Actually it has been determined that the Universe is indeed infinite and it is also expanding as well . $\endgroup$ – Peter U Jan 8 '16 at 2:55
  • 6
    $\begingroup$ @Peter U : it hasn't been determined that the universe is infinite. That's a popscience non-sequitur that started being bandied around in circa 2013 when WMAP measurements indicated the universe was flat. $\endgroup$ – John Duffield Jan 8 '16 at 14:23
  • $\begingroup$ @JohnDuffield, there are a few things you seemed to read around or not follow carefully in my question. I never said that space is nothing. I distinctly separated the two and asked where space is. The answer is of course that we don't know. As well, unfortunately, the big bang theory doesn't work in that the evidence doesn't support a gigantic explosion. It doesn't follow that the universe "is expanding" if all that is expanding is the visible light itself. As well, it doesnt' follow that it is expanding "no where." Tautology, not my problem. Saying "try" is your shortcoming. $\endgroup$ – Private Name Jan 8 '16 at 15:12
  • $\begingroup$ It does no good to say that the balloon that is our "universe" contains space within it and that prior to its "expansion," there was nothing. Such is a positive claim that cannot be supported by evidence. Just say, "if the big bang occurred, it is not known how it could have occurred," since such would negate all the known laws of physics in several respects. One, even if everything were squeezed into a tiny dot, then there would still be everything and not nothing. Just in a tiny dot. Two, where that dot would be would necessarily be somewhere, and a place is a thing, not a nothing. Etc. $\endgroup$ – Private Name Jan 8 '16 at 15:16
  • $\begingroup$ As well, that light travels doesn't mean that the universe is traveling. That it takes light a certain time before reaching us says nothing about whether space moves. If light (thing) moves into the unseen/unknown of that which is later the known universe, then the place in which it travels was there prior to the light's traveling there, regardless of our knowledge of that place. Hence, there is a causal relation to said place, just an inductive one. Based on the fact that "nothing exceeds the speed of light" where light moves must be there prior to the light itself. $\endgroup$ – Private Name Jan 8 '16 at 15:20
0
$\begingroup$

Well, I'm not going to pretend I am right, or what I say is how it is, but I have been the person to ask those same questions before, and heres what I know now. First, ditch the whole 'nothing' component of the big bang. Its easy to think of the big bang as being an event in time, but it isn't, its the t=0 on your time line. Before that would be negative time, and its not that there are not theories about negative time, but for observation's sake we'll leave it out.

At t=0 all the matter today was present then, there was just no distance between each point, and this is regardless of your position in the universe. It wasn't a distance from some point that was 0, rather all points, pick any two points and their distance measured to be 0. In regard to what the universe is expanding "in to", if our universe was truly at a point of infinite density, it wouldn't be expanding into anything.

If its hard to come to grips with space expanding, and the confusion about where this empty space is coming from, then look at it in a different way. How long does it take to go from A to B, if its 0 seconds then distance is 0. But if its greater than 0, you have distance. And if its infinity, you have infinite distance.

In all honesty there are still questions that need to be answered, and while there are many good models of the universe out there, they seem to hold an incomplete picture, evident by the still on going debate.

So to conclude, there was no before, and there was no nothing either. Matter in the universe has apparently remained constant, and there doesn't seem to be any indication that this would be broken as it has remained that way ever since. I would ignore the time stuff I said for now, its better for comprehending this rather than the reality of it. Hope this helped.

While this isn't the best answer in the universe, hopefully its a step for you to find the answer you are looking for.

$\endgroup$
  • $\begingroup$ Great answer(!), yes it did help. I upvoted it, but for this particular stacks site I sadly don’t have enough points for the upvote to change the answer publicly. But yes the answer makes sense to me. You basically say there is no space prior to the Big Bang, nor time. In said hypothesis or explanation of the Big Bang, that would seem coherent to me in that matter was once distanceless, which I guess is impossible but easier to grant charitably than to grant that everything was once a bubble inside nothing and that said bubble expanded exponentially but that into which it expanded isn’t there. $\endgroup$ – Private Name Dec 15 '17 at 9:18
  • $\begingroup$ You also grant right away that you are open to changing your answer, which to me is a great sign of rationality. Your point about 1 and 0 if to represent time and distance helped a lot! $\endgroup$ – Private Name Dec 15 '17 at 9:19
  • $\begingroup$ So in short yeah, great answer and one that I liked the most in ever discussing it with anyone. The answers I tend to get are smug or blindly follow the consensus without regard to what I’m actually asking. Thanks :-) $\endgroup$ – Private Name Dec 15 '17 at 9:21
  • $\begingroup$ Glad that I helped! I was nervous about the reception to my response but I am happy to hear that it had a positive impact, all be it surprised. While stack exchange can have consequences for asking improper questions, keep asking those questions, here or somewhere else, as it is this curiosity that will eventually find answers to the questions that arise from this confusing universe. :) $\endgroup$ – Terran Dec 17 '17 at 2:41
-2
$\begingroup$

The Big Bang did not happen at a single point, nor did the Universe begin at a single point. The Universe is, and has always been, infinite. The Big Bang was just when the Universe's expansion really began — that is, when objects started drifting away from each other. The Universe was still infinite, but there was less space between the matter.

This density caused the Universe to get extremely hot and expand. So here, space itself was distorted and began to expand. More and more space was created between the matter, and still is now (although now it is mainly due to dark energy instead of heat).

$\endgroup$
  • $\begingroup$ We have no evidence that the universe is and always been infinite. I'm afraid this is a popscience myth that started to gain ground from about 2013 when WMAP evidence suggested the universe was flat. Some people then claimed that a flat universe had to be an infinite universe, even though it's a non-sequitur. To appreciate this, note that we can see the curvature of the Earth. And note that if we couldn't, then if some guy told you the Earth was infinite, you'd tell him to take a running jump. $\endgroup$ – John Duffield May 10 '16 at 20:23
  • 2
    $\begingroup$ @JohnDuffield I'll admit I'm not an expert, but this paper does seem to claim that an infinite universe is the most logical conclusion. The paper is short--would you mind addressing its contents? Perhaps I'm misunderstanding them. $\endgroup$ – called2voyage Jun 10 '16 at 14:33

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.