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B "Before" the Big Bang

  1. Oct 14, 2016 #1
    Hey guys,

    It is widely publicized that space and time originated during the Big Bang, but what exactly surrounds this lone hot and dense singularity? Space is the background of something, so I think void (which is just empty space) is already there even "before" the Big Bang event started occurring.

    Thoughts?
     
  2. jcsd
  3. Oct 14, 2016 #2

    russ_watters

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    It's a common misconception you are operating under: since the universe is everything, there is no void for it to expand into, nor is there a "before".
     
  4. Oct 14, 2016 #3
    Time is an observed phenomenon, by means of which human beings sense and record changes in the environment and in the universe. There is no humans "before" the Big Bang event started so the term "time" is useless, not to mention there are no changes "before" the singularity started to expand. Space is the distance between objects, once again there are no objects back then "before" Big Bang so the term "space" can't be used. If there is no changes (such as motion, object changing, etc.), then there is no time.

    What I mean by void, is the background of something. Let us assume, there is this singularity that will eventually expand and become the nowadays' universe. What "surround" this singularity, I think, is the void.
     
  5. Oct 14, 2016 #4

    Drakkith

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    It's important to understand that the singularity most likely appears because we don't understand physics at the extreme temperature and density of the very early universe, not necessarily because there was an actual singularity. In any case, at t=0 the entirety of the universe exists as a singularity, not a single point.
     
  6. Oct 14, 2016 #5
    I see. In your opinion, does space originated from the singularity? Space has no shape, unlike object which is something that has shape and must be necessarily finite, same with energy. I define space as the distance between objects. And if there are no objects, it is only void there. Nonexistence. So, I think what "surround" the pre-BB singularity is the void.
     
  7. Oct 14, 2016 #6

    russ_watters

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    No, it's not. Just because there were no human constructed clocks available doesn't mean we can't use other processes to tell time.
    So....I guess we're agreed now: no space or time before the Big Bang.
    Nope. Singularity or not, there is no "void". If there was a void into which everything else is expanding, it would be considered part of the universe.
     
  8. Oct 14, 2016 #7
    If void is considered to be a part of the Universe, then it is unimaginable or impossible for void to be finite because void is that which has no shape. Only that which has shape is finite, such as the atoms, planets, etc.

    What are the other processes that can be done to tell time?
     
  9. Oct 14, 2016 #8

    Drakkith

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    No, because the singularity is most likely just a breakdown in our ability to model the universe, not an actual state of existence.

    Current mainstream models do not place the universe within a "void" like you're describing and any such view is logically inconsistent with itself given our current understanding of space, time, and causality.
     
  10. Oct 14, 2016 #9
    I agree with your 1st answer.

    So, matter is eternal together with energy. I can't imagine that the singularity don't happen in a "place". Can you give your opinions about this? What is space in the context of Big Bang theory?
     
  11. Oct 14, 2016 #10

    russ_watters

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    Nonsense. A void can take any shape it or we want. I cup my hands and inside (by volume, to within a fraction of a percent) is a region of totally empty space. A void. How would you tell the difference between that and a section of the "void" you describe?

    Also, you haven't said so, but I'm guessing you think the universe is spherical? It isnt.
    Any process that takes a known amount of time can be used to tell time. As you say, motion is one example (that's how the universe is aged). Stellar evolution is another.
     
  12. Oct 14, 2016 #11

    Drakkith

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    Matter isn't conserved, unlike energy.

    The singularity happens everywhere. At all points in space.

    In the BBT, space is one part of spacetime, which is a way of modeling the universe that leads to useful predictions. I could tell you what spacetime is in a mathematical sense (I believe it's a certain type of manifold) but there's no real way to describe it accurately using non-mathematical terminology. Many call it a "framework". I suppose that's as accurate as you can get without getting into math.
     
  13. Oct 14, 2016 #12

    PeterDonis

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    Please give specific references, and not pop science ones. There are a lot of pop science treatments of this topic that can be confusing or misleading. If you have acceptable references and provide them to me by PM, we can consider reopening the thread. Until then, this thread is closed.
     
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