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arXiv · 1310.5117

Turning Point Instabilities for Relativistic Stars and Black Holes

Joshua S. Schiffrin·Robert M. Wald
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Abstract

In the light of recent results relating dynamic and thermodynamic stability of relativistic stars and black holes, we re-examine the relationship between "turning points"---i.e., extrema of thermodynamic variables along a one-parameter family of solutions---and instabilities. We give a proof of Sorkin's general result---showing the existence of a thermodynamic instability on one side of a turning point---that does not rely on heuristic arguments involving infinite dimensional manifold structure. We use the turning point results to prove the existence of a dynamic instability of black rings in 5 spacetime dimensions in the region where $c_J > 0$, in agreement with a result of Figueras, Murata, and Reall.

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Joshua S. Schiffrin, Robert M. Wald. 2013-12-10. Turning Point Instabilities for Relativistic Stars and Black Holes. https://doi.org/10.1088/0264-9381%2F31%2F3%2F035024

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