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[CMB] Need some help

  1. Dec 19, 2005 #1
    Ok, i'm reading up on the Cosmic Microwave background radiation guys. And i'm at a part that confuses me (actually i kinda don't understand the whole thing, but i'm trying) regarding the uniformity or isotropy. If someone can put this in a simpler form so that i can understand it easier i'd highly appreciate it, thanks in advance for your help :smile:
  2. jcsd
  3. Dec 20, 2005 #2


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    The intensity of radiation from objects within each concentric 'shell' decrease proportionate to the square of the distance [from earth], however, the average number of objects within each shell [assuming uniform density as indicated by observation] increases with respect to the cube of the distance [from earth]. Hence, the total background radiation [CMB] is dominated by contributions from distant sources. What they lack in intensity is more than made up by sheer numbers.
    Last edited: Dec 20, 2005
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