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arXiv · 1901.02784

Extended Thermodynamics of Self-Gravitating Skyrmions

Daniel Flores-Alfonso·Hernando Quevedo
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Abstract

A modification of the hedgehog ansatz has recently led to novel exact black hole solutions with selfgravitating SU(2) Skyrme fields. Considering a negative cosmological constant the black holes are not asymptotically anti-de Sitter (AdS) but rather asymptote to an AdS version of Barriola--Vilenkin spacetime. We examine the thermodynamics of the system interpreting the cosmological constant as a bulk pressure. We use the standard counterterm method to obtain a finite Euclidean action. For a given coupling of the matter action, the system behaves as does a charged AdS black hole in the fixed charged ensemble. We find that in the limit case when the Skyrme model becomes a nonlinear sigma model the system exhibits a first order phase transition of Hawking--Page type. The universality class of these Einstein--Skyrme black holes is that of van der Waals.

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Daniel Flores-Alfonso, Hernando Quevedo. 2019-01-09. Extended Thermodynamics of Self-Gravitating Skyrmions. https://doi.org/10.1088/1361-6382%2Fab2c20

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