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Universe expanion

  1. Jul 22, 2009 #1
    Did anti gravity exist at the beginning of the universe when the conditions were hot/high energy, which repulsed matter at a rate proportional to the square of the distance (inflation maybe) until, the universe had expanded and cooled enough for this force (anti gravity) to return to normal attractive gravity? And are the particles at the “edge” of the universe somehow interacting with the void that its expanding into, and creating the heat/energy needed for anti gravity, which is causing the expansion of the universe.

    Are all estimates of the size of the universe based on the Doppler effect?
  2. jcsd
  3. Jul 22, 2009 #2


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    No, there is no reason to change gravity (general relativity) to explain inflation.

    The size of the observable universe is based on distance measurements from the redshift of distant objects - so yes ultimately on the doppler effect.
    The size of the universe depends on models about the shape of the universe which are based on the total mass/density.
  4. Jul 23, 2009 #3
    Hello mgb_phys,

    Thanks for your reply, is there a theory for inflation in general relativity? I'm a bit of a newbie on this subject.
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