# Thermodynamics, stability and Hawking-Page transition of Kerr black holes from R\'enyi statistics

## TL;DR

This paper explores the thermodynamics and phase transitions of Kerr black holes using Rényi entropy, revealing stability conditions and phase transitions similar to those in AdS space, thus extending black hole thermodynamics frameworks.

## Contribution

It introduces a Rényi entropy-based thermodynamic analysis for Kerr black holes, demonstrating stability and phase transition phenomena analogous to AdS space scenarios.

## Key findings

- Isolated Kerr black holes are stable under Rényi entropy.
- Slowly rotating black holes can be in stable equilibrium with a heat bath.
- Hawking-Page and small-large black hole phase transitions are observed.

## Abstract

Thermodynamics of rotating black holes described by the R\'enyi formula as equilibrium and zeroth law compatible entropy function is investigated. We show that similarly to the standard Boltzmann approach, isolated Kerr black holes are stable with respect to axisymmetric perturbations in the R\'enyi model. On the other hand, when the black holes are surrounded by a bath of thermal radiation, slowly rotating black holes can also be in stable equilibrium with the heat bath at a fixed temperature, in contrast to the Boltzmann description. For the question of possible phase transitions in the system, we show that a Hawking-Page transition and a first order small black hole/large black hole transition occur, analogous to the picture of rotating black holes in AdS space. These results confirm the similarity between the R\'enyi-asymptotically flat and Boltzmann-AdS approaches to black hole thermodynamics in the rotating case as well. We derive the relations between the thermodynamic parameters based on this correspondence.