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arXiv · 2206.10055

Phase transitions and thermodynamic geometry of a Kerr-Newman black hole in a cavity

Yuchen Huang·Jun Tao·Peng Wang·Shuxuan Ying
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Abstract

Being placed in a cavity is an effective way of reaching thermodynamic equilibrium for black holes. We investigate a Kerr-Newman black hole in a cavity as well as compare it with two reduced cases, i.e., a RN black hole in a cavity and a Kerr black hole in a cavity. We derive the quasi-local energy from the Hamiltonian, and construct the first law of thermodynamics accordingly. In a canonical ensemble, these black holes could undergo a van der Waals-like phase transition, which is very similar to that in AdS space. We further investigate the black holes' thermodynamic geometry, which is a powerful tool to diagnose microscopic interactions of a thermodynamic system. Our results show that in a cavity, although phase structures of these black holes are similar, their thermodynamic geometry show strong dissimilarities, implying that the microstructure of a black hole is sensitive to its states.

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Yuchen Huang, Jun Tao, Peng Wang, Shuxuan Ying. 2022-06-21. Phase transitions and thermodynamic geometry of a Kerr-Newman black hole in a cavity. https://doi.org/10.1140/epjp%2Fs13360-023-03858-w

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