Semiclassical Extremal Blackholes

TL;DR

This paper investigates the quantum-corrected geometry of extremal black holes in a two-dimensional model, revealing a mild horizon singularity and discussing extensions beyond the horizon with implications for black hole entropy and information loss.

Contribution

It provides a semiclassical analysis of extremal black holes in a reduced 2D setting, highlighting horizon singularities and possible extensions beyond the horizon.

Findings

Quantum corrections induce a mild singularity at the horizon.

Extensions beyond the horizon are not unique but can avoid severe singularities.

Results have implications for understanding black hole entropy and information loss.

Abstract

Extremal black holes are studied in a two dimensional model motivated by a dimensional reduction from four dimensions. Their quantum corrected geometry is calculated semiclassically and a mild singularity is shown to appear at the horizon. Extensions of the geometry past the horizon are not unique but there are continuations free from malevolent singularities. A few comments are made about the relevance of these results to four dimensions and to the study of black hole entropy and information loss.