On the existence of thermodynamically stable asymptotically flat black holes

TL;DR

This paper investigates the thermodynamics of two families of asymptotically flat black holes, revealing their thermodynamic stability and similarities despite differing characteristics, using the Brown-York quasilocal formalism with counterterms.

Contribution

It demonstrates the thermodynamic stability of two distinct families of exact black hole solutions using a quasilocal formalism, highlighting their similar thermodynamic behavior.

Findings

Both black hole families are thermodynamically stable.

Despite different characteristics, their thermodynamic behaviors are strikingly similar.

The study extends understanding of black hole thermodynamics in different gravity theories.

Abstract

We use the quasilocal formalism of Brown and York, supplemented with counterterms, to investigate the thermodynamics of asymptotically flat black holes. We consider two families of exact regular black hole solutions, which are thermodynamically stable. The first one consists of four-dimensional static charged hairy black holes in extended supergravity. The second family consists of five-dimensional static charged black holes in Gauss-Bonnet (GB) gravity. Despite the fact that their characteristics are completely different, we found a striking similarity between their thermodynamic behaviour.