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Relativistic gravity incomplete? Big Bang singularity

  1. Dec 8, 2009 #1
    I have a question regarding the conditions "prior" to the Big Bang. I realize tere is no empirical evidence for these conditions, only speculations.

    At the point of the Big Bang, all of matter and energy was "infinitely" densely concentrated at a single point, correct? Even though GR breaks down at this singularity, are these not black hole conditions, in which nothing can exit the horizon?

    What force must then have overpowered this enormously strong gravitational force in order to bring matter outside the horizon/expand the matter at the singularity point?
     
  2. jcsd
  3. Dec 8, 2009 #2

    mathman

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    The big bang theory seems to be on solid ground right for t > tz (Planck time). However for t=0, it is much more speculative.
     
  4. Dec 8, 2009 #3

    JesseM

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    Although GR is probably not the correct theory to use very close to the Big Bang, it is nevertheless true that on a purely theoretical level there is no problem in GR with the notion of a singularity which emits matter and energy. For one thing, GR theoretically allows for the possibility of "white holes" which behave like the time-reverse of black holes, the event horizon being one-way in the opposite direction (matter can be emitted by the central singularity and escape the horizon, but once you're outside the horizon it's impossible to enter it). Secondly, the Big Bang singularity differs from either a black hole or white hole singularity, as explained in this section of the Usenet Physics FAQ:
     
  5. Dec 8, 2009 #4
    I see. Thank you very much. :)
     
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