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I need help with a calculation please

  1. Jul 8, 2006 #1

    I was thinking about Cosmology and Omega-Matter. The critical density of the Universe is equal to about 6 Hydrogen atoms/ meter cubed. If we were to smear a human body out to fit it to this density, how big a volume would the human body smear out to be?

    Assume, the human body occupies a volume of ~1 meter cubed

    Assume, the average Mol. in the human body is 6,6-Carbon

    Can anyone figure this out? It seems like a fun way to gain perspective on just how undense the Universe is.

    P.S. Really our best WMAP data says the Universe's matter density is closer to 0.27 x 6 Hydrogen atoms. If we exclude dark matter, this number gets even smaller and becomes 0.04 x 6 Hydrogen atoms/ meter cubed.
  2. jcsd
  3. Sep 12, 2006 #2
    'any ideas folks?'
  4. Sep 19, 2006 #3


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    'A cube of side about 3 light-seconds (10^9m).'
  5. Oct 17, 2006 #4
    'I guess no one likes this idea, lol.'
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