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Singularities are one-sided?

  1. Oct 26, 2008 #1
    Singularities are places where time ends for anything in them. In other words, if Bob falls into a black hole at 2:00, time will end for the matter in his body and he won't exist time-wise past 2:00. But according to the Big Bang theory, the universe began in the form of a singularity. Obviously time exists now, but we don't know if time existed before the BB singularity. Does this mean singularities are one sided as far as time goes? meaning that time must either begin or end completely in singularities. If so, what does this mean for the creation of the BB singularity?
    Last edited: Oct 27, 2008
  2. jcsd
  3. Oct 26, 2008 #2
    marcus linked to this page in a recent thread, which says:
    (I don't have the background myself to comment any more than that.)
  4. Oct 27, 2008 #3


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    The big bang may have resulted from some prior 'universe' reaching a 'tipping point'. Problem is, information on conditions leading up to the big event may not have survived. Some think it may be embedded in the CMB. It is, however, probably safe to say the BB singularity was not the same species as those that may currently reside in the universe.
  5. Oct 28, 2008 #4
    No one knows for sure.

    The start of this universe may have come from another, may be part of an infinite chain of bubbles evolving spactime, may have been a random quantum vacuum fluctuation...

    It is currently believed we can not directly observe the "start" because it's beyond our cosmological horizon...the key point is no one can prove whether the start was really a singularity or not...big bounce is a recent theory supposing a rather smooth and finite start....
  6. Oct 28, 2008 #5
    Thanks for the comments. I agree with you Chronos in that the BB singularity is probably different from today's typical black hole singularities. It just seems to me that we know too little about singularities. All we can really do is calculate a handful of their properties like their mass, gravity, and maybe some other things. I'm really interested in how they effect time, and I'd really like to know what part Hawking radiation played in the BB S, if any at all. As far as other theories for the start of the universe go, I don't like anything that proposes infinite cycles, like Steinhardt and Turok's Brane Cosmology for example. Those type of theories, while they may be correct, just don't seem to fly in my thinking. The way I see it, if we go back in time, all of space had to be in one place, which is why I prefer the BB over newer theories. I'll always be open to new things, but unlike other theories, the BB has the most evidence, and has made the most accurate predictions. However, it may be that we just don't have enough technology to find evidence supporting newer theories.
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