Multiple Reentrant Phase Transitions and Triple Points in Lovelock Thermodynamics

TL;DR

This paper explores complex phase transitions in Lovelock gravity's black holes, revealing phenomena like multiple reentrant phase transitions and unique critical points influenced by higher curvature corrections.

Contribution

It uncovers new multiple reentrant phase transitions and isolated critical points in Lovelock black holes, expanding understanding of their thermodynamic phase structure.

Findings

Discovery of multiple reentrant phase transitions in Lovelock black holes.

Identification of a new isolated critical point with non-standard exponents.

Observation of Van der Waals and tricritical phenomena in higher curvature gravity.

Abstract

We investigate the effects of higher curvature corrections from Lovelock gravity on the phase structure of asymptotically AdS black holes, treating the cosmological constant as a thermodynamic pressure. We examine how various thermodynamic phenomena, such as Van der Waals behaviour, reentrant phase transitions (RPT), and tricritical points are manifest for U(1) charged black holes in Gauss-Bonnet and 3rd-order Lovelock gravities. We furthermore observe a new phenomenon of "multiple RPT" behaviour, in which for fixed pressure the small/large/small/large black hole phase transition occurs as the temperature of the system increases. We also find that when the higher-order Lovelock couplings are related in a particular way, a peculiar isolated critical point emerges for hyperbolic black holes and is characterized by non-standard critical exponents.