Classical and Semiclassical Properties of Extremal Black Holes with Dilaton and Modulus Fields

TL;DR

This paper explores the classical and semiclassical features of extremal black holes with dilaton and modulus fields, revealing an asymptotically anti-de Sitter geometry and implications for black hole thermodynamics and information loss.

Contribution

It demonstrates that extremal black holes with dilaton and modulus fields have an asymptotically anti-de Sitter geometry, affecting their classical and thermodynamic properties, and analyzes their evaporation process.

Findings

Geometry is asymptotically anti-de Sitter instead of flat

Stable ground state likely emerges after evaporation

Implications for information loss in black hole physics

Abstract

We discuss both classical and semiclassical properties of extremal black holes in theories where the dilaton and a modulus field are present. We find that the corresponding 2-dim geometry is asymptotically anti-de Sitter rather then asymptotically flat as in the purely dilatonic case. This fact has many important consequences, which we analyze at length, both for the classical behaviour and for the thermodynamical properties of the black hole. We also study the Hawking evaporation process in the semiclassical approximation. The calculations strongly indicates the emergence of a stable ground state as the end point of the process. Some comments are made about the relevance of our results for the problem of information loss in black hole physics.