Entropy of nonlinear black holes in quadratic gravity

TL;DR

This paper calculates the entropy of nonlinear black holes within quadratic gravity using Noether charge and Euclidean methods, focusing on extremal cases and boundary condition effects.

Contribution

It introduces a novel approach to compute black hole entropy in quadratic gravity coupled with nonlinear electrodynamics, emphasizing extremal configurations.

Findings

Entropy expression derived for nonlinear black holes in quadratic gravity.

Analysis of extremal black hole configurations.

Impact of boundary conditions on black hole parameters.

Abstract

Employing the Noether charge technique and Visser's Euclidean approach the entropy of the nonlinear black hole described by the perturbative solution of the system of coupled equations of the quadratic gravity and nonlinear electrodynamics is constructed. The solution is parametrized by the exact location of the event horizon and charge. Special emphasis in put on the extremal configuration. Consequences of the second choice of the boundary conditions, in which the solution is paramerized by the charge and the total mass as seen by a distant observer is briefly examined.