Quasi-local thermodynamics of Kerr-Newman black holes: Pressure, volume, and shear work

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteur principal: Campos, Thiago
Format: Preprint
Publié: 2026
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866917365464170496
author Campos, Thiago
author_facet Campos, Thiago
contents While the quasi-local thermodynamics of spherically symmetric black holes is well described by pressure and volume, extending this framework to rotating spacetimes poses a significant challenge. Rotation induces an oblate deformation of the horizon, breaking the direct functional dependence between geometric volume and area. In this work, we resolve this difficulty by establishing a quasi-local thermodynamic framework for Kerr-Newman black holes. We demonstrate that accommodating this kinematic deformation requires extending the thermodynamic phase space to include a geometric eccentricity parameter $Y$ and its conjugate, a thermodynamic shear tension $X$. Consequently, the rotational contribution is incorporated into the first law with a shear work term $X dY$. We derive the generalized first laws and Smarr formulas (Euler relations) for both the internal energy and enthalpy representations, showing that these thermodynamic potentials can be obtained through Legendre transformations that isolate the quasi-local energy from the rotational energy. Thus, this framework provides a novel perspective on the thermodynamics of rotating black holes, integrating the geometric deformation of the horizon into a quasi-local description.
format Preprint
id arxiv_https___arxiv_org_abs_2603_21258
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Quasi-local thermodynamics of Kerr-Newman black holes: Pressure, volume, and shear work
Campos, Thiago
General Relativity and Quantum Cosmology
While the quasi-local thermodynamics of spherically symmetric black holes is well described by pressure and volume, extending this framework to rotating spacetimes poses a significant challenge. Rotation induces an oblate deformation of the horizon, breaking the direct functional dependence between geometric volume and area. In this work, we resolve this difficulty by establishing a quasi-local thermodynamic framework for Kerr-Newman black holes. We demonstrate that accommodating this kinematic deformation requires extending the thermodynamic phase space to include a geometric eccentricity parameter $Y$ and its conjugate, a thermodynamic shear tension $X$. Consequently, the rotational contribution is incorporated into the first law with a shear work term $X dY$. We derive the generalized first laws and Smarr formulas (Euler relations) for both the internal energy and enthalpy representations, showing that these thermodynamic potentials can be obtained through Legendre transformations that isolate the quasi-local energy from the rotational energy. Thus, this framework provides a novel perspective on the thermodynamics of rotating black holes, integrating the geometric deformation of the horizon into a quasi-local description.
title Quasi-local thermodynamics of Kerr-Newman black holes: Pressure, volume, and shear work
topic General Relativity and Quantum Cosmology
url https://arxiv.org/abs/2603.21258