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arXiv · astro-ph/0010630

Cosmological thermodynamics and deflationary gas universe

Winfried Zimdahl·Alexander B. Balakin
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Abstract

We establish a general thermodynamic scheme for cosmic fluids with internal self-interactions and discuss equilibrium and non-equilibrium aspects of such systems in connection with (generalized) symmetry properties of the cosmological dynamics. As an example we construct an exactly solvable gas dynamical model of a ``deflationary'' transition from an initial de Sitter phase to a subsequent Friedmann-Lema\^ıtre-Robertson-Walker (FLRW) period. We demonstrate that this dynamics represents a manifestation of a conformal symmetry of an ``optical'' metric, characterized by a specific effective refraction index of the cosmic medium.

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Winfried Zimdahl, Alexander B. Balakin. 2000-10-31. Cosmological thermodynamics and deflationary gas universe. https://doi.org/10.1103/physrevd.63.023507

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