Electrically Charged Einstein-Born-Infeld Black Holes with Massive Dilaton

TL;DR

This paper numerically constructs and analyzes electrically charged black hole solutions in Einstein-Born-Infeld gravity with a massive dilaton, revealing diverse horizon structures and extremal configurations.

Contribution

It introduces new numerical solutions for charged black holes with a massive dilaton, showing richer causal structures than in the massless case.

Findings

Black holes can have one, two, or three horizons.

Existence of extremal black holes with inner and triply degenerated horizons.

Dilaton potential increases the variety of black hole causal structures.

Abstract

We numerically construct static and spherically symmetric electrically charged black hole solutions in Einstein-Born-Infeld gravity with massive dilaton. The numerical solutions show that the dilaton potential allows many more black hole causal structures than the massless dilaton. We find that depending on the black hole mass and charge and the dilaton mass the black holes can have either one, two, or three horizons. The extremal solutions are also found out. As an interesting peculiarity we note that there are extremal black holes with an inner horizon and with triply degenerated horizon.