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Space a property of Big Bang?

  1. Apr 7, 2015 #1
    hello guys,

    i just want to know if space had been there before the big bang, or is it a property of the big bang

  2. jcsd
  3. Apr 7, 2015 #2


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    The "Big Bang Theory" is a description of how the universe has expanded from a hot, dense plasma to what it is today. The expansion beginning is taken as nominally one Plank Time after the "Big Bang Singularity".

    The singularity is the place where the Big Bang Theory math model breaks down and gives unphysical results, and so it not understood.

    The Big Bang Theory, starting as it does after the singularity, makes no statement about the existance of space or time prior to one Plank Time.

    You WILL see statements in pop-science that say that the big bang theory posits that there was no space or time prior to the singularity but this is not supported by any math that gives meaningful results.

    There are theories other than the Big Bang Theory, and some of them posit a temporally infinite universe.
  4. Apr 7, 2015 #3
    in short, you are saying that space had been there even before the big bang?
  5. Apr 7, 2015 #4


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    No, I am not. I am an adherent of the Big Bang Theory, which is supported far more strongly by empirical evidence than any of the other theories. and the Big Bang Theory is silent on the pre-existence of space and time. They may have existed, they may have not. I hold with the likelihood that they did, but there is no evidence to support that.
  6. Apr 7, 2015 #5
    oh, there is an evidence, if space between galaxies is expanding, that is enough evidence to support the idea that all matters were close to each other high in temperature,... !?
  7. Apr 7, 2015 #6


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    That is correct, sort of. The Big Bang Theory extrapolates from the current universe backwards to determine what kind of universe had to exist at various stages to create the universe we live in.

    I say "sort of" because of your statement that "space is expanding". This is a contentious subject but the consensus is that a much better description of what is happening is not "space is expanding" but rather "things are getting farther apart".

    I recommend the link in my signature.
  8. Apr 7, 2015 #7


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    From a GR point of view space, time and gravity are inexorably entwined. It is thought that gravity was united with the three other basic forces in the universe prior to the big bang, so from that perspective, the concept of space is undefined before gravity split off from the other forces. Sten Odenwald discusses the relationship between gravity and space here http://www.astronomycafe.net/gravity/gravity.html.
  9. Apr 8, 2015 #8
    No one knows. Most physical cosmologists think space emerged with the Big Bang, but science does not recognize committees or majority opinions. We cannot know what happened at the precise moment of the Big Bang, just up to the Plank time.
  10. Apr 8, 2015 #9

    You will often hear it said that the universe occurred because of a quantum fluctuation, but this requires something in which the quantum fluctuation took place.
  11. Apr 8, 2015 #10
    Right. Logical conclusions lead us to determine that an infinitesimally small amount of space must have existed before the big bang. Before you can get E or M you need space.
  12. Apr 8, 2015 #11


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    Logic often does no good in cosmology and quantum mechanics. Better just leave it as we don't know rather than making categorical statements that you cannot support.
  13. Apr 9, 2015 #12
    I think logic brings sense into thing.
  14. Apr 9, 2015 #13


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    Unfortunately, you will sometimes be wrong in cosmology and quantum mechanics bec
    But it so obviously did not in this case.
  15. Apr 9, 2015 #14


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    No it doesn't - you may be reaching this conclusion because you are assuming that to exist, things must exist in space. In other words, assuming the conclusion from the start.
    In some theories what may exist "before" the big bang simply does not have the properties, such as distance, that characterize space. This may or may not be true and it may also be impossible to determine (all theories regarding what may have existed then are speculative) but it is not a logical impossibility.
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