Born-Infeld black holes coupled to a massive scalar field

TL;DR

This paper investigates how adding a potential for a massive scalar field affects Born-Infeld black holes, revealing richer structures, extremal solutions, and stability properties through analytical and numerical analysis.

Contribution

It introduces the effects of a scalar potential on Born-Infeld black holes, including the existence of extremal solutions and stability analysis, extending previous massless scalar field models.

Findings

Richer causal structure with potential inclusion

Existence of extremal black holes for specific scalar mass and charge

General stability suggested by the turning point method

Abstract

Born-Infeld black holes in the Scalar-Tensor Theories of Gravity, in the case of massless scalar field, have been recently obtained. The aim of the current paper is to study the effect from the inclusion of a potential for the scalar field in the theory, through a combination of analytical techniques and numerical methods. The black holes coupled to a massive scalar field have richer causal structure in comparison to the massless scalar field case. In the latter case, the black holes may have a second, inner horizon. The presence of potential for the scalar field allows the existence of extremal black holes for certain values of the mass of the scalar field and the magnetic (electric) charge of the black hole. The linear stability against spherically symmetric perturbations is studied. Arguments in favor of the general stability of the solutions coming from the application of the "turning point" method are also presented.