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Alan Guth's Inflationary Theory

  1. Nov 7, 2003 #1
    It was my understanding that one of the reasons for Inflationary Theory was to address The Smoothness Problem.

    Haven't recent detailed surveys of the CBR shown that the universe wasn't smooth in it's first few moments?

  2. jcsd
  3. Nov 7, 2003 #2
    The smoothness problem doesn't require the universe to be perfectly smooth, just "very" smooth. Specifically, the problem is that in a decelerating universe, gravity causes locally dense regions to clump, so to explain the amount of smoothness we see today, the earlier universe must have been much, much smoother, and the question is what mechanism caused it to be so smooth. It didn't have to be perfectly smooth --- in fact, the tiny quantum irregularities from inflation are thought to be what is responsible for all the large-scale structure (galaxies, groups of galaxies, etc.) we see today. This tiny amount of non-smoothness was amplified exponentially by inflation.
  4. Nov 7, 2003 #3
    The original theory of Alan Guth is not longer valid because suffered of a problem called "graceful exit", and it predicted an inhomogeneous universe, rather that the homogeneous universe that we observe. Actually chaotic inflation, hybrid inflation or supernatural inflation are the references
  5. Nov 7, 2003 #4
    Really, there are a gazillion inflationary theories ... some have been ruled out by WMAP, but there are plenty left.
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