Three-charge black holes from the worldsheet

TL;DR

This paper constructs explicit worldsheet conformal field theories for three-charge black holes in string theory, linking supergravity solutions with string worldsheet models and exploring their supersymmetric and extremal limits.

Contribution

It introduces null-gauged WZW models that reproduce three-charge black hole backgrounds and relate to smooth horizonless geometries, advancing the understanding of string dynamics on such backgrounds.

Findings

Constructed null-gauged WZW models matching black hole geometries.

Linked models to smooth horizonless geometries via analytic continuation.

Analyzed supersymmetric and extremal configurations, including BMPV black hole.

Abstract

We consider the general asymptotically flat, doubly-rotating, three-charge black hole uplifted to a family of NS5-F1-P black brane solutions of Type IIB supergravity. We construct a null-gauged WZW model whose target-space geometry reproduces this background in the NS5 decoupling limit, and show that the gauging parameters precisely satisfy the appropriate consistency conditions on the perturbative string spectrum. Through an analytic continuation and an appropriate limit, this model relates to a recently studied construction describing strings on smooth, horizonless geometries. We further analyze the supersymmetric and extremal three-charge configuration, corresponding to the ten-dimensional uplift of the (NS5-decoupled) BMPV black hole, and show that it requires a novel class of null-gauged WZW models. Our construction provides explicit examples of worldsheet CFTs that capture string dynamics on certain black hole geometries with linear dilaton asymptotics.