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Homework Help: Oblers Paradox

  1. Nov 18, 2011 #1
    ρ1. The problem statement, all variables and given/known data
    Suppose all stars had the same radius as the Sun, and they were distributed throughout the universe with the same density as we have nearby- about 1 star per cubic parsec. Approximatly how bigh in parsecs and light years would the universe have to be in order to avoid Oblers Paradox?

    2. Relevant equations
    Think of light as a particle- how far does the photon have to go until it hits another particle?

    3. The attempt at a solution
    photon- particle relation xr= 1/an
    tr= 1/anc
    κ= nσr/ρ where (n/ρ) is the number of atoms per unit mass and κ= total cross section per unit mass
  2. jcsd
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