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The Purpose of Inflation

  1. Nov 13, 2005 #1
    The gravity of the orginal singularity would make it a black hole.
    The original gravity of the universe would give it an escape
    velocity; the escape velocity of the Big Bang.
    In order to get the universe over its gravity there was an inflationary
    epoch that rapidly brought the strength of gravity down everywhere
    allowing the universe to really begin.

    This is the purpose of inflation: to get the universe over its original

    Anybody want to argue that the universe didn't begin with gravity?
    Then Hawking's No Boundary Proposal is violated and the
    there really are "Universal Boundaries" or space then No space.
    You can't have it both ways Hawking!!! :tongue:

    Mitch Raemsch
    Last edited: Nov 13, 2005
  2. jcsd
  3. Nov 13, 2005 #2
    If the singularity were indeed a black hole,then how could the universe (as weknow it) have begun?
    But, it becomes more and more difficult to obtain an escape velocity, as the gravity increase, doesn't it?So, there should have been some other mechanism acting at the time, which must have been much stronger than gravity, isn't it?Then, how can the universe begin only with gravity?
  4. Nov 13, 2005 #3
    All that is necessary is for inflation to be a "stronger force" than gravity!!! :!!)

    What else is going to get the universe over its own gravity?
  5. Nov 13, 2005 #4
    Inflation is not a force.It is an event.
  6. Nov 14, 2005 #5
    As far as I'm aware gravity became a repulsive force under the tremendous negative pressure and for a tiny moment of time caused the inflation.
  7. Nov 14, 2005 #6
    :!!):!!):!!) God or natural selection! :tongue2: :tongue2: :tongue2:
  8. Nov 14, 2005 #7
    Better still you can follow Linde and others who prefer to start from the "largeness" of eternal inflation rather than the smallness of a singularity. This reverses things so that instead of an explosion of a hot point you get a bubble of cooling in a hot field.

    And perhaps even the idea of inflation as a particular kind of state will eventually be replaced by some more general model of dimensional potential.

    But certainly, the questions are still open enough that there is room for no singularity. And even inflation could be replaced by something that "looks a little like it" yet is actually quite different under the skin.

    Cheers - John McCrone.
  9. Nov 14, 2005 #8


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    The initial singularity was not a black hole. Black holes are static solutions to Einstein's equations and the cosmological solution is dynamic. Thus, the fact that the universe did not collapse at t = 0 might be somehow explained by the value of the Hubble parameter (the speed of expansion) which was infinite at t = 0. On the other hand inflation takes place because there is an accelerated expansion of space, mantaining a constant (finite) Hubble parameter at some time after the big-bang.
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