Topological Stars and Black Holes

TL;DR

This paper investigates five-dimensional smooth bubble spacetimes with topological cycles, resembling black holes, and explores their properties and potential as models for black hole microstates.

Contribution

It introduces Topological Stars in five-dimensional Einstein-Maxwell theory and analyzes their structure, size, and relation to black hole microstate geometries.

Findings

Topological Stars have topological cycles supported by magnetic flux.

They can be macroscopically large compared to the Kaluza-Klein circle.

The paper describes non-singular black string solutions with bubble interiors.

Abstract

We study smooth bubble spacetimes in five-dimensional Einstein-Maxwell theory that resemble four-dimensional magnetic black holes upon Kaluza-Klein reduction. We denote them as Topological Stars since they have topological cycles supported by magnetic flux. They can be macroscopically large compared to the size of the Kaluza-Klein circle and could describe qualitative properties of microstate geometries for astrophysical black holes. We also describe five-dimensional black strings without curvature singularity, the interior caps as a two-dimensional Milne space with a bubble.