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Oscilating Universe WITH Perpetual Expansion

  1. Feb 27, 2004 #1


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    A thought recently occurred to me regarding cosmological models. Frequently, the Oscillating Universe and one with perpetual expansion are presented as opposing views. This is usually based on the presupposition that an oscillating universe requires a Big Crunch. But in many models of a multibrane cosmos, the Big Bang is thought to have been caused by collision between two membranes, or a near collision in which close proximity triggers a response (through some mechanism I do not understand).

    Is it not probable that this is exactly what would happen in a continually expanding universe? To illustrate, I will use BEC's as a model (this is what sparked the idea in the first-place). A BEC can be formed by pushing certain particles to a very low energy state. At very low temperatures, the ability to distinguish between these individual particles will vanish and in many ways, they behave as a single particle. If two parallel universes, or two branes of a single multiverse continually expand, their temperatures will continually decrease approaching, but never quite reaching, absolute zero. It may be possible that when the two are at very low energy states, they may attempt to combine into a sort of "cosmological condensate" and that this attempted unification may set up the conditions of close proximity in which the big bang is generated.

    Are there any current cosmological models matching this description?
    Last edited: Feb 27, 2004
  2. jcsd
  3. Feb 28, 2004 #2
    What is simpler to create the structure of the universe from what seem to be elementary particles or to create these particles from the unfolding of larger structures that interact and create the
    structures we see.
  4. Mar 5, 2004 #3


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    An intersting question. I would say that any oscilating cosmological model would answer, "both". The universe crates the particals, which create space, which creates a new universe, etc.

    But my real question is about the expansion of space causing (or enabling) different branes to approach each other in ever-closer proximaty. This could probably be best modeled by viewing the energy state of each brane as a wave signature. The more energy per volume, the greater the amplitude of the wave. As the universe expands, energy per volume decreases, and the universe gets "smoother". When two parrelel branes become smooth enough, the difference between their two states becomes indistinguishable, even on quantum levels, and so they become a single entity. This could be seen as a sort of "collision" of the two branes, which might set off the next Big Bang without any Big Crunch having taken place.

    But I assume I cannot be the first person to think this (unless it contains some glaring flaw that would make it "unthinkable" to a more trained mind), so I wonder if such a model already exists or has existed. If so, what is/was it called, so I can Google it?
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