Geometric aspects of charged black holes in Palatini theories

TL;DR

This paper explores the unique geometric and topological features of charged black holes in Palatini gravity theories, revealing wormhole structures, potential horizon disappearance, and conditions for curvature regularity.

Contribution

It provides a detailed mathematical derivation of these black hole solutions and analyzes their geodesic and geometric properties, highlighting novel features in Palatini formalism.

Findings

Black holes have wormhole-like inner structures.

Curvature divergences can be absent for specific mass and charge values.

Event horizons may vanish, leading to black hole remnants.

Abstract

Charged black holes in gravity theories in the Palatini formalism present a number of unique properties. Their innermost structure is topologically nontrivial, representing a wormhole supported by a sourceless electric flux. For certain values of their effective mass and charge curvature divergences may be absent, and their event horizon may also disappear yielding a remnant. We give an overview of the mathematical derivation of these solutions and discuss their geodesic structure and other geometric properties.