Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Shear Viscosity in the Post-quasistatic Approximation   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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The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
13
The categories of this paper are: quant-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: q-fin
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The categories of this paper are: hep-ex
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The categories of this paper are: nlin
1
The categories of this paper are: cs
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The categories of this paper are: chem-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: stat
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The categories of this paper are: comp-gas
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The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
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The categories of this paper are: supr-con