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arXiv · 2006.10880

Geometric and Thermodynamic Volume of Hairy Black Branes

Alvaro Ballon Bordo
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Abstract

With the objective to generalize previous results found for a handful of explicit solutions, we study the extended thermodynamics of a black brane with minimally coupled scalar hair in D-dimensional asymptotically anti-de Sitter spacetimes. Using Komar integration and the Hamiltonian formalism to calculate the conserved charges, we obtain a Smarr relation that is applicable to a wide variety of solutions and suggests a more general definition of the thermodynamic volume. This volume is found to be proportional to the geometric volume, and a simple prescription is given to calculate the constant of proportionality. Moreover, the method of Hamiltonian perturbations yields an extended first law of thermodynamics for hairy black branes, thus giving a definition for their enthalpy. These results are then verified by applying them to some of the explicit solutions that exist in the literature.

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Alvaro Ballon Bordo. 2020-06-18. Geometric and Thermodynamic Volume of Hairy Black Branes. https://arxiv.org/abs/2006.10880

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