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arXiv · 2308.12630

Extended black hole thermodynamics from extended Iyer-Wald formalism

Yong Xiao·Yu Tian·Yu-Xiao Liu
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Abstract

In recent years, there has been significant interest in the field of extended black hole thermodynamics, where the cosmological constant and/or other coupling parameters are treated as thermodynamic variables. Drawing inspiration from the Iyer-Wald formalism, which reveals the intrinsic and universal structure of conventional black hole thermodynamics, we illustrate that a proper extension of this formalism also unveils the underlying theoretical structure of extended black hole thermodynamics. As a remarkable consequence, for any gravitational theory described by a diffeomorphism invariant action, it is always possible to construct a consistent extended thermodynamics using this extended formalism.

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Yong Xiao, Yu Tian, Yu-Xiao Liu. 2023-08-24. Extended black hole thermodynamics from extended Iyer-Wald formalism. https://doi.org/10.1103/physrevlett.132.021401

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