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Universe Entropy Equasion

  1. Feb 24, 2004 #1

    Does anyone have an equasion for the Entropy of the Universe?

    Barring my computation, please provide your best equasion for cross-verification with a numerical entropic solution in (J*K^-1) SI units.

    I attempted to locate a solution on the internet, however only located entropy for various particles and black holes.

    Anyone interested in examining some black hole entropy equasions may click the reference provided.

    These equasions represent my classical approach.

    [tex]T_i = 3000 K[/tex] CBR photo-transparency temperature
    [tex]T_f = 2.725 K[/tex] CBR temperature
    [tex]r_i = 7*10^5 Ly[/tex] CBR photo-transparency range
    [tex]r_f = \frac{c}{H_o} = 1.761*10^{10} Ly[/tex] Universe range

    Classical entropy equasion for spherical universe containing an ideal gas:
    [tex]\Delta S_u = K_b \left( ln \frac{T_f}{T_i} + ln \left( \frac{r_f}{r_i} \right)^3 \right) = K_b \left( ln \frac{T_f}{T_i} + ln \left( \frac{c}{H_o r_i} \right)^3 \right)[/tex]

    Ho = Hubble Constant

    [tex]\Delta S_u = 3.230*10^{-22} J*K^{-1}[/tex]

    Does anyone have more accurate values?


    "We cannot order men to see the truth or prohibit them from indulging in error." - Max Planck, Philosophy of Physics, 1936
    Last edited: Feb 24, 2004
  2. jcsd
  3. Feb 24, 2004 #2
    Firstly how does count?..something that is forever moving?

    You would have to accomodate every instant..instanton.. and every Futurama?, if only just to get some approximation of what you are counting!.
  4. Feb 24, 2004 #3
    Well, let's see, if there is no alternative but that a universe exist, then the probability that the universe should exist is 1, and there is never any change in the total information contained in the universe. So the total entropy of the universe is always zero, right?
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