Exact analytical solution for an Israel-Stewart cosmology

Cruz, Norman; Gonzalez, Esteban; Palma, Guillermo

Abstract

In this article we report a novel analytic solution describing a cosmological model with a matter content represented by a one dissipative fluid component, in the framework of the causal Israel-Stewart theory. The dissipative fluid is described by a barotropic equation of state p = (gamma - 1)rho and the bulk viscosity has been assumed of the form xi = xi 0 rho(s). We study within the parameter space which label the solution, a suited region compatible with an accelerated expansion of the universe for late times, as well as stability properties of the solution at the critical parameter value gamma = 1 and for s = 1/2. We study as well the consequences that arise from the positiveness of the entropy production along the time evolution. We found that the solution for pressureless dark matter, gamma = 1, can well describe a universe with a transition from a decelerated expansion to an accelerated one at late times, but with a very large non-adiabatic contribution to speed of sound. Finally, the kinematics and thermodynamics properties of the solutions are discussed in terms of the type of expansion and entropy production.

Más información

Título según WOS: Exact analytical solution for an Israel-Stewart cosmology
Título de la Revista: GENERAL RELATIVITY AND GRAVITATION
Volumen: 52
Número: 6
Editorial: SPRINGER/PLENUM PUBLISHERS
Fecha de publicación: 2020
DOI:

10.1007/S10714-020-02712-Z

Notas: ISI