Shadow thermodynamics of the Hayward-AdS black hole

TL;DR

This paper explores the thermodynamics of Hayward-AdS black holes using shadow formalism, revealing how shadow radius correlates with phase transitions and thermodynamic properties, offering a novel observational approach.

Contribution

It introduces shadow radius as an effective tool to analyze black hole thermodynamics, providing new insights into phase transitions and thermal profiles of Hayward-AdS black holes.

Findings

Shadow radius is monotonic with horizon radius.

Increasing magnetic charge enlarges shadow and lowers coexistence temperature.

Temperature exhibits N-type behavior below critical temperature.

Abstract

In this paper, the phase structure of the Hayward-AdS black hole (BH) is studied using shadow formalism. It has been found that the shadow radius is a monotonic function of the horizon radius and can therefore play an equivalent role to the horizon radius in characterizing the thermodynamics of Hayward-AdS BH. The thermodynamic phase transition (PT) of the Hayward-AdS BH is investigated with the shadow radius. It is shown that as the magnetic charge increases, the shadow radius becomes larger, while the coexistence temperature becomes lower. The thermal profile of the Hayward-AdS BH is established by combining the temperature diagram and the shadow cast diagram, which shows that for a fixed magnetic charge, the temperature of the Hayward-AdS BH increases with the pressure while the region of the thermal profile decreases with the pressure. In particular, the temperature of the Hayward-AdS BH follows an N-type change trend when it is smaller than the critical temperature. This imply that the BH shadow may be used to investigate the thermodynamics of the Hayward-AdS BH.