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Big bang and small bang black holes

  1. Jan 8, 2008 #1
    if BB is true then there should be blackholes which should also explode like the big bang...Do we have evidence for this type of small bang blackholes...
     
  2. jcsd
  3. Jan 8, 2008 #2
    Are you saying that every singularity may be a big bang?
    There is a theory ralated to that: Fecund universes
     
  4. Jan 9, 2008 #3
    Maybe the explosion takes place inside a BH, maybe there is a bounce inside changing a a BH in a WH and maybe it will not be observed from the outside???
     
  5. Jan 9, 2008 #4

    marcus

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    What Hurk4 says is right. One would not expect to see the re-expansion, because it would be creating a new expanding region---a tract of space separate from our space.

    the difficult issue is what observable consequences can be derived from the models that have this feature, that astronomers can look for

    something about our own big bang? some distinctive signature to tell us where it could have come from.
    some signature in the gammaray bursts which seem to be associated with the collapse of massive stars into black holes? something associated with black holes, in other words.

    the tricky thing is the evidence.
    there are a number of research papers that give theoretical models of how the collapse of a star could "bounce" and result in a second region of spacetime* that expands from the pit----theorists argue about these models. the hard thing is to find out what OTHER distinctive things the various models predict, so they can be tested.

    *concealed from our observable universe by the black hole's event horizon
     
    Last edited: Jan 9, 2008
  6. Jan 9, 2008 #5
    I have some secondary questions here.
    1) Is there (already?) something known about the relation of the mass (of the rebouncing hole) and the speed of evaporation by Hawking radiation. I think that theory says that small holes evaporate faster than big holes? (To be remarked here is that the smallest possible hole has the Planck dimension and that it lifetime is of the order of Planck time i.e. 10E-43second. Big holes live very very long and must look very static). I dont think 'Hawking evaporation has anything to do with an explosion.
    2) Can it be expected from theory that such a Hawking evaporation flux eventually can be observed in case of very small holes?
    3) Maybe observation of Hawking radiation flux can give us qualitative and quantitave information about small holes?
     
  7. Jan 9, 2008 #6

    marcus

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    at least some of these could be answered better by some of the others here and I hope they do. they are good questions.
    1) AFAIK the answer is NO. the speed of evaporation----the lifetime of the BH---is governed by the mass of the BH

    but different models (all are preliminary) allow for different relations between the ingoing mass of the BH and the outgoing.

    2) I personally expect that if and when we observe small BH we will observe their high-flux final burst of radiation. So the answer here is yes.

    3) YES! in my opinion, it will be the best or one of the best sources of information
     
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