Rational nonlinear electrodynamics of AdS black holes and extended phase space thermodynamics

TL;DR

This paper explores the thermodynamic behavior of magnetically charged AdS black holes within rational nonlinear electrodynamics, revealing Van der Waals-like phase transitions and introducing new thermodynamic quantities related to nonlinearity and magnetic charge.

Contribution

It introduces a novel analysis of RNED-AdS black holes' critical behavior, including new thermodynamic variables and confirms the analogy with Van der Waals systems.

Findings

Critical exponents match Van der Waals system

New thermodynamic quantities for nonlinear parameter and magnetic charge

Confirmed first law and Smarr formula consistency

Abstract

The critical behavior of magnetically charged by rational nonlinear electrodynamics (RNED) AdS black holes in an extended phase space is investigated. The cosmological constant is considered as a thermodynamic pressure and the black hole mass is identified with the chemical enthalpy. The analogy with the Van der Waals liquid-gas system is found and the critical exponents coincide with those of the Van der Waals system. The thermodynamics of RNED-AdS black holes and phase transitions are studied. A new thermodynamic quantities conjugated to the nonlinear parameter of RNED and a magnetic charge are defined. It is demonstrated the consistency of the first law of black hole thermodynamics and the Smarr formula.