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CMB anisotropies and matter structures

  1. Nov 23, 2003 #1

    hellfire

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    CMB anisotropies are deviations of the temperature of the black body emission mainly (but not only) by photons, which have to climb out gravitational potential of higher density concentrations during recombination epoch and during their spatio-temporal trajectory till now (Sachs-Wolfe effect). Since these 'cold spots' in the CMB are located on the sky at very specific locations, my question is whether they can be used to infere bout the position of great mass structures now (clusters, dark matter), and, if not, why not.

    Thanks.
     
    Last edited: Nov 23, 2003
  2. jcsd
  3. Nov 26, 2003 #2
    Seeds Of Galactic Structure (CMB Hot & Cold Spots)

    “Since these 'cold spots' in the CMB are located on the sky at very specific locations, my question is whether they can be used to infere bout the position of great mass structures now (clusters, dark matter), and, if not, why not.”

    The clumps (BOTH hot and cold spots) are imprints on the CMB which are evidence for the emergence of structure within the Universe. These imprints show up on a finer scale than the primordial features etched onto the CMB by the Big Bang itself. The hot and cold spots in the CMB represent seeds from which galaxies and galaxy clusters were born. As photons penetrated galactic clusters, hot and cold spots were generated that differ by only a millionth of a degree from the average temp of the CMB (2.76 Kelvins or about a 1/10th of the temperature of the Universe – as it was in the act of birth).
    Now, unless you can rewind time back to its nascent stage, I can’t really see how any accurate picture of how great mass structures came to be in the positions they are now, could possibly be drawn. We’re talking about some +/- 16 billion years. However, the CMB hot and cold spots can reveal secrets about the forces involved in the Inflationary stage of the Big Bang.
     
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