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arXiv · 1109.2804

A general maximum entropy principle for self-gravitating perfect fluid

Sijie Gao
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Abstract

We consider a self-gravitating system consisting of perfect fluid with spherical symmetry. Using the general expression of entropy density, we extremize the total entropy $S$ under the constraint that the total number of particles is fixed. We show that extrema of $S$ coincides precisely with the relativistic Tolman-Oppenheimer-Volkoff (TOV) equation of hydrostatic equilibrium. Furthermore, we apply the maximum entropy principle to a charged perfect fluid and derive the generalized TOV equation. Our work provides a strong evidence for the fundamental relationship between general relativity and ordinary thermodynamics.

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Sijie Gao. 2011-09-13. A general maximum entropy principle for self-gravitating perfect fluid. https://doi.org/10.1103/physrevd.84.104023

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