Exact Four-Dimensional Dyonic Black Holes and Bertotti-Robinson Spacetimes in String Theory

TL;DR

This paper constructs exact four-dimensional dyonic black hole solutions and Bertotti-Robinson spacetimes in string theory using conformal field theory models, linking lower-dimensional black holes to higher-dimensional solutions.

Contribution

It introduces a method to obtain four-dimensional dyonic black holes and Bertotti-Robinson universes via tensoring 2D conformal field theories with coset models, providing exact string theory solutions.

Findings

Exact 4D dyonic black hole solutions derived from 2D models.

Connection between 2D black holes and higher-dimensional solutions.

Realization of Bertotti-Robinson spacetime in string theory context.

Abstract

Conformal field theories corresponding to two-dimensional electrically charged black holes and to two-dimensional anti-de Sitter space with a covariantly constant electric field are simply constructed as $SL(2,R)/Z$ WZW coset models. The two-dimensional electrically charged black holes are related by Kaluza-Klein reduction to the 2+1-dimensional rotating black hole of Banados, Teitelboim and Zanelli, and our construction is correspondingly related to its realization as a WZW model. Four-dimensional spacetime solutions are obtained by tensoring these two-dimensional theories with $SU(2)/Z(m)$ coset models. These describe a family of dyonic black holes and the Bertotti--Robinson universe.