Constraints on the topology of higher dimensional black holes

TL;DR

This paper reviews the known constraints on the possible topologies of event horizons in higher-dimensional black holes, highlighting that not all topologies are allowed despite the lack of spherical symmetry.

Contribution

It provides a comprehensive review of the topological constraints on higher-dimensional black hole horizons, summarizing recent theoretical developments.

Findings

Event horizons cannot have arbitrary topology in higher dimensions.

Certain topologies are forbidden for black hole horizons.

The review consolidates known constraints in the field.

Abstract

Although a black hole need not be spherical in higher dimensions, its event horizon cannot have arbitrary topology. Here we review some of the known constraints on horizon topology for higher dimensional black holes.