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The big bang singularity?

  1. Dec 7, 2011 #1
    If we could find the point in space where the singularity happened would you expect to find abnormalities in space time? Is there a ground zero, where there is no relative motion where everthing is rushing away?
  2. jcsd
  3. Dec 7, 2011 #2


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    There is no such point. The big bang singularity was a singularity across all of space at a single instant in time (as opposed to, say, a black hole singularity, which is a singularity at a single point in space across all of time).

    The expansion of the universe isn't everything rushing away from a single point of explosion but rather the distance between everything growing over time, like a balloon being blown up.
  4. Dec 7, 2011 #3
    yes, even thought there is no single geometric point.


    PS: it's not classical physics, either. But quantum mechanics doesn't provide the answer, either.
  5. Dec 8, 2011 #4

    When the Universe began it was completely crammed and uniformly with matter. There was no empty space whatsoever for a long time. Everyplace was like every other place.

    Most scientists think the Universe was infinite when it began and still is. So it didn't begin at a point.

    As far as I know there is no known reason that the Universe expands. It just does it.

    We have no idea what it expands into. According to General Relativity if there is no matter or energy then there is no such thing as time or distance.

    There isn't any edge or anything like that, so you can chose any point as the center. They are all the same.
  6. Dec 8, 2011 #5
    Any sources supporting these statements?

    There was NO matter at the bang...Nor was the universe infinite when it began. No one knows whther the universe is infinite or finite and unbounded now.

    For example:
  7. Dec 8, 2011 #6
    Patrick Powers
    How big was this early universe that was crammed with matter?
  8. Dec 8, 2011 #7
    Remarkable claims require remarlable proof.
  9. Dec 8, 2011 #8


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    These statements are mutually contradictory. If the universe was not infinite when it began, then we DO know that it is not infinite now.
  10. Dec 8, 2011 #9


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    There is no way to know the size of the universe currently. If might be infinite, it might not be. However the Big Bang model doesn't care whether the universe is infinite or not. Either way it still happened everywhere in the universe.
  11. Dec 8, 2011 #10
    Nobody knows. It could have been infinite, could have been finite. In such a situation time and space are so distorted that our theories don't give answers about size, and it is not even clear what the questions should be. So I don't worry about it much.
  12. Dec 8, 2011 #11
    It is possible to measure the curvature of the Universe. From this it is calculated that the Universe is at least three times the size of the visible Universe, and most think it is considerably more than that.

    To show that the Universe was infinite you would have to calculate a curvature of exactly zero. No way of measuring and calculating that number to infinite precision presents itself. No way of calculating ANY number that involves measurement to infinite precision presents itself.

    t is possible that someone someday could convince the world that a non-flat universe leads to a contradiction, so it must be flat/infinite QED.
  13. Dec 8, 2011 #12


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    The Big Bang happened in the universe?

    Hmmmm... :uhh:

    Last edited: Dec 9, 2011
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