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A self-similar dynamics in viscous spheres

W. Barreto·J. Ovalle·B. Rodriguez
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Abstract

We study the evolution of radiating and viscous fluid spheres assuming an additional homothetic symmetry on the spherically simmetric space--time. We match a very simple solution to the symmetry equations with the exterior one (Vaidya). We then obtain a system of two ordinary differential equations which rule the dynamics, and find a self--similar collapse which is shear--free and with a barotropic equation of state. Considering a huge set of initial self--similar dynamics states, we work out a model with an acceptable physical behavior.

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W. Barreto, J. Ovalle, B. Rodriguez. 2005-08-12. A self-similar dynamics in viscous spheres. https://doi.org/10.1023/a%3A1018812714524

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