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Questions about the theory

  1. Apr 10, 2007 #1
    I ran across this on a website. The problem is, because heat spreads out slower than light, when the big bang explodes and expands at the speed of light then there should be unequal heat regions all over the universe. But this is not true according to observation. Why is this so?
     
  2. jcsd
  3. Apr 11, 2007 #2

    pervect

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    The standard explanation is inflation. The problem is known as "the horizon problem". See for instance http://www.astro.ucla.edu/~wright/cosmoall.htm (I'll provide a short quote to point out the specific applicable section).

    The "flatness-oldness" problem (i.e. why omega is close to one) is also explained by inflation.
     
  4. Apr 11, 2007 #3

    Chronos

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    That does not make any sense to me, csrichie. Heat is transferred by kinetic and photonic energy, according to current theories. The speed of transfer is interrupted by molecules jostling for a more stable position in the grand scheme of things.
     
  5. Apr 12, 2007 #4

    Phobos

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    Note that the Big Bang was not like a conventional "explosion" (it was, in part, the rapid expansion of all space) Also, it didn't expand at the speed of light (at least, not for more than an instant as you'll see from pervect's info about the inflationary period). Also note that there are observable variations in the cosmic microwave background radiation.
     
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