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Exact non-equilibrium solutions of the Einstein-Boltzmann equations. II

Derik Wolvaardt·Roy Maartens
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Abstract

We find exact solutions of the Einstein-Boltzmann equations with relaxational collision term in FRW and Bianchi I spacetimes. The kinematic and thermodynamic properties of the solutions are investigated. We give an exact expression for the bulk viscous pressure of an FRW distribution that relaxes towards collision-dominated equilibrium. If the relaxation is toward collision-free equilibrium, the bulk viscosity vanishes - but there is still entropy production. The Bianchi I solutions have zero heat flux and bulk viscosity, but nonzero shear viscosity. The solutions are used to construct a realisation of the Weyl Curvature Hypothesis.

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Derik Wolvaardt, Roy Maartens. 1996-11-14. Exact non-equilibrium solutions of the Einstein-Boltzmann equations. II. https://doi.org/10.1088/0264-9381%2F14%2F2%2F026

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