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A question based on Lawrence Krauss' explanation

  1. Oct 29, 2011 #1
    Good afternoon gentlemen/women,

    I have a question regarding Lawrence Krauss' talk called "A Universe From Nothing" (Which can be found at ). In the talk, Krauss says that quantum fluctuations can produce a universe. He mentions that if we were to observe this happening, the universe from our perspective would get smaller and smaller and smaller, whereas from those inside the new universe would view it expanding exponentially.

    Really an amazing thing to discover, coming from someone like myself who's just now going to college for physics. Unfortunately, however, my mind was racing on the subject and I lost some sleep last night over a question that's been going through my mind.

    Is it possible that a black hole could indeed be one of these 'universes'? I know that singularities shrink to an infinitesimally small point; wouldn't that be a matching descriptor to what Krauss said? (Of course, I realize we would never be able to see it from the inside, which has my idea turned on his head, because in a way, it might seem like a logical fallacy.)

    Are there any out there who can ease my mental torment? =P

    Thank you, and all efforts are much appreciated.
    Last edited by a moderator: Sep 25, 2014
  2. jcsd
  3. Oct 29, 2011 #2


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    The whole issue of "black hole === universe" has been brought up so often here that I think it would be fair to say that the topic has been bludgeoned to death.

    No, black holes are not considered to be universes or to cause universes.

    EDIT: by the way, welcome to the forum.

    I remember watching that video some time back and being very puzzled by the statement that it would appear simultaneously to be expanding AND shrinking based on your frame of reference. I don't get it.
  4. Oct 29, 2011 #3
    Thank you!

    I'm sorry to have brought the dead horse topic back to life. I just couldn't shake it out of my head; I needed the thoughts of others much more qualified than I to help make a rational judgement.
  5. Oct 30, 2011 #4


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    The idea of black holes 'birthing' new universes has been around for years. I see problems - like what happens to 'baby' when 'mom' merges with another black hole, or merely evaporates via hawking radiation?
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