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arXiv · 2005.06358

Stability of the isotropic pressure condition

L. Herrera
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Abstract

We investigate the conditions for the (in)stability of the isotropic pressure condition in collapsing spherically symmetric, dissipative fluid distributions. It is found that dissipative fluxes, and/or energy density inhomogeneities and/or the appearance of shear in the fluid flow, force any initially isotropic configuration to abandon such a condition, generating anisotropy in the pressure. To reinforce this conclusion we also present some arguments concerning the axially symmetric case. The consequences ensuing our results are analyzed.

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L. Herrera. 2020-05-13. Stability of the isotropic pressure condition. https://doi.org/10.1103/physrevd.101.104024

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