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arXiv · 1003.1825

Shear Viscosity in the Post-quasistatic Approximation

C. Peralta·L. Rosales·B. Rodrí guez-Mueller·W. Barreto
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Abstract

We apply the post-quasi--static approximation, an iterative method for the evolution of self-gravitating spheres of matter, to study the evolution of anisotropic non-adiabatic radiating and dissipative distributions in General Relativity. Dissipation is described by viscosity and free-streaming radiation, assuming an equation of state to model anisotropy induced by the shear viscosity. We match the interior solution, in non-comoving coordinates, with the Vaidya exterior solution. Two simple models are presented, based on the Schwarzschild and Tolman VI solutions, in the non--adiabatic and adiabatic limit. In both cases the eventual collapse or expansion of the distribution is mainly controlled by the anisotropy induced by the viscosity.

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C. Peralta, L. Rosales, B. Rodrí guez-Mueller, W. Barreto. 2010-04-20. Shear Viscosity in the Post-quasistatic Approximation. https://doi.org/10.1103/physrevd.81.104021

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