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Equation of state and transport processes in self--similar spheres

W. Barreto·C. Peralta·L. Rosales
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Abstract

We study the effect of transport processes (diffusion and free--streaming) on a collapsing spherically symmetric distribution of matter in a self--similar space--time. A very simple solution shows interesting features when it is matched with the Vaidya exterior solution. In the mixed case (diffusion and free--streaming), we find a barotropic equation of state in the stationary regime. In the diffusion approximation the gravitational potential at the surface is always constant; if we perturb the stationary state, the system is very stable, recovering the barotropic equation of state as time progresses. In the free--streaming case the self--similar evolution is stationary but with a non--barotropic equation of state.

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W. Barreto, C. Peralta, L. Rosales. 2005-08-12. Equation of state and transport processes in self--similar spheres. https://doi.org/10.1103/physrevd.59.024008

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