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Cosmological bulk viscosity, the Burnett regime, and the BGK equation

A. Sandoval-Villalbazo·L. S. Garcia-Colin
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Abstract

Einstein's field equations in FRW space-times are coupled to the BGK equation in order to derive the stress energy tensor including dissipative effects up to second order in the thermodynamical forces. The space-time is assumed to be matter-dominated, but in a low density regime for which a second order (Burnett) coefficient becomes relevant. Cosmological implications of the solutions, as well as the physical meaning of transport coefficients in an isotropic homogeneous universe are discussed.

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A. Sandoval-Villalbazo, L. S. Garcia-Colin. 2002-10-25. Cosmological bulk viscosity, the Burnett regime, and the BGK equation. https://arxiv.org/abs/gr-qc/0210089

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