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Is there a mechanism for reproducing universes?

  1. Aug 30, 2004 #1
    Just recently Hawking rejected baby universes; the mechanism was that black holes would spawn a new dimension unseen from our universe.
    Smolin first proposed this idea, and as far as I can tell in recent discussions between Susskind and Smolin he still believes in it.
    Susskind had argued what happens when two black holes merge? Do two baby universes become one? It doesn’t add up! On the other hand he seems to favor eternal inflation. I’m not very familiar with this, but I think it’s where our universe will expand to eventually cause another region of the universe to separate, kind of like a bubble divining in two, and so the whole universe is like a glass of soda water filled with billions of bubbles.

    One other mechanism to mention is the cyclic scenario, but likewise it doesn’t seem to be consistent with observation; that is the universe has low density, which will cause it to expand forever. This would seem to be in favor of eternal inflation only I can’t see such a process being consistent with the conditions the universe began with.

    So are all these theories flawed? Or is there a mechanism we haven’t considered yet? :frown:

    I accidentally posted this in the wrong forum so if someone can move it to the appropriate forum, thanks…
    Last edited: Aug 30, 2004
  2. jcsd
  3. Aug 30, 2004 #2
    Scientific American Magazine

    The latest issue of Scientific American is a specail issue dealing with Einstein and recent comological theories including bubble universes inside of other bubble universes, you may want to check it out.

    Nature does appear to be cyclic but whether this happens on a universal scale is yet to be discovered. If one subscribes to a holographic model of the universe, one comes to the conclusion that if the universe is contracting in part (black holes) it is also contracting as a whole. Redshifts only show that objects are moving away from us. It is widely believed that the universe is expanding as a whole but I think we can be easily deceived since we have such a limited view of things. Since science is seeking a theory to unite the relativity (the big) with quantum machanics (the small) it would make sense that the big and the small are one and the same. The term "universe" means a type of wholeness or onenes. But what do I know? I am just a temporal organism in a vast cosmos.
  4. Aug 30, 2004 #3
    My point being is that I have little reason to believe the universe will contract again, and not much in the way of believing it will eternally inflate. Therefore what other mechanism could there be? Or are we down to either cyclic or eternal inflation?
  5. Aug 30, 2004 #4
    Universe theories

    There are 3 current speculations as to what the "macroscopic" universe will do in the distant future, two of which you have already mentioned. The third is that the universe will keep slowing down its expansion just until it barely stops.

    Some more creative theories as to the general structure of the universe was proposed by a scientist in the 1970s by a physicist name I cannot remember. He stated that subatomic vacuum fluctuations that cause virtual particles to pop in and out of existence is similar to the big bang in that energy is popping into existence from the vacuum of space. This would cause speculations that virtual particles popping in and out of existence are actually universes coming into and going out of existence. Though virtual particles pop in and out of existence in fractions of a nanosecond (as we measure it), an entity existing "inside" the virtual particle may experience time on a scale of billions of years since time is relative. As wild as this sounds, to me it is just as plausible than any other theory since we know so little about the cosmos.
  6. Aug 30, 2004 #5
    What about the theory of multidimension membranes colliding to create vast bulks on which universes were created?

    wouldn't that be considered a mech to create universe
  7. Aug 31, 2004 #6
    This kind of leaves us wondering if our universe is popping in and out of existence in a fraction of a nano-second in some other universe doesn’t it? Sounds like a Very radical idea, and one that doesn’t seem to make a whole lot of sense. :rolleyes:
  8. Aug 31, 2004 #7
    This is the older ekpyrotic scenario which the cyclic model was derived from. It states that there are two 10 dimensional branes which collide to create the big bang. I don’t understand this one all to well. Does this mean our universe is created on one of the branes whereby we’ll collide sometime in the future with the other?
  9. Aug 31, 2004 #8
    Radical theory maybe

    I retire with "the greatest knowledge is to know you know nothing"-Socrates
  10. Aug 31, 2004 #9
    I like that! although I'm sure in the next 10 to 15 years we'll know something, at least in our life times anyway... :)
  11. Sep 4, 2004 #10
    Exactly this theory has two major implications
    1. The creation of our universe is nothing special
    2. We are currently on a crash course with another multidimensional membrane.
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