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arXiv · 1302.5750

Spherically symmetric models: separating expansion from contraction in models with anisotropic pressures

José P. Mimoso·Morgan Le Delliou·Filipe C. Mena
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Abstract

We investigate spherically symmetric spacetimes with an anisotropic fluid and discuss the existence and stability of a dividing shell separating expanding and collapsing regions. We find that the dividing shell is defined by a relation between the pressure gradients, both isotropic and anisotropic, and the strength of the fields induced by the Misner-Sharpe mass inside the separating shell and by the pressure fluxes. This balance is a generalization of the Tolman-Oppenheimer- Volkoff equilibrium condition which defines a local equilibrium condition, but conveys also a non- local character given the definition of the Misner-Sharpe mass. We present a particular solution with dust and radiation that provides an illustration of our results.

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José P. Mimoso, Morgan Le Delliou, Filipe C. Mena. 2013-02-23. Spherically symmetric models: separating expansion from contraction in models with anisotropic pressures. https://doi.org/10.1063/1.4734466

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