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Density fluctuations in the universe after the recombination period

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It is shown that the cosmic matter gas after the recombination period can be regarded in a very good approximation as a general relativistic Boltzmann gas in the very vicinity of equilibrium. As a consequence, spatial temperature fluctuations (ΔT/T)≊10−5 imply immense density fluctuations up to (Δp/p)≊105.

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  1. Israel, W.: 1972, in L. O'Raifeartaigh (ed.),General Relativity, Clarendon Press, Oxford.

  2. Lessner, G.: 1984,Astrophys. Space Sci. 100, 359.

  3. Stewart, J. M.: 1973,Cargèse Lectures in Physics, Vol. 6, Gordon and Breach, New York, p. 175.

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Lessner, G. Density fluctuations in the universe after the recombination period. Astrophys Space Sci 161, 175–180 (1989).

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  • Recombination
  • Temperature Fluctuation
  • Density Fluctuation
  • Spatial Temperature
  • Cosmic Matter