New Horizons for Black Holes and Branes

TL;DR

This paper systematically explores new classes of higher-dimensional black holes using the blackfold effective theory, revealing novel solutions like helical black rings and non-uniform black cylinders, and discussing their properties and implications.

Contribution

It introduces a systematic method to find new black hole solutions in higher dimensions, including exotic configurations with unique symmetries and properties.

Findings

Discovered large classes of new black holes, including helical black rings and black odd-spheres.

Reproduced known ultraspinning Myers-Perry black holes as blackfold configurations.

Identified solutions with minimal surface geometries and discussed their uniqueness and entropy properties.

Abstract

We initiate a systematic scan of the landscape of black holes in any spacetime dimension using the recently proposed blackfold effective worldvolume theory. We focus primarily on asymptotically flat stationary vacuum solutions, where we uncover large classes of new black holes. These include helical black strings and black rings, black odd-spheres, for which the horizon is a product of a large and a small sphere, and non-uniform black cylinders. More exotic possibilities are also outlined. The blackfold description recovers correctly the ultraspinning Myers-Perry black holes as ellipsoidal even-ball configurations where the velocity field approaches the speed of light at the boundary of the ball. Helical black ring solutions provide the first instance of asymptotically flat black holes in more than four dimensions with a single spatial U(1) isometry. They also imply infinite rational non-uniqueness in ultraspinning regimes, where they maximize the entropy among all stationary single-horizon solutions. Moreover, static blackfolds are possible with the geometry of minimal surfaces. The absence of compact embedded minimal surfaces in Euclidean space is consistent with the uniqueness theorem of static black holes.