Rotating black holes in three-dimensional Ho\v{r}ava gravity

TL;DR

This paper explores black hole solutions in three-dimensional Hořava gravity, revealing conditions for anti-de Sitter, de Sitter, and flat asymptotics, and examining the existence of universal horizons in these solutions.

Contribution

It derives the most general stationary, circularly symmetric black hole solutions in three-dimensional Hořava gravity with various asymptotics.

Findings

Admissible black hole solutions with AdS asymptotics require infinite scalar propagation speed.

The theory admits black holes with de Sitter and flat asymptotics, unlike standard 3D GR.

Universal horizons may or may not exist depending on parameters, with some beyond the de Sitter horizon.

Abstract

We study black holes in the infrared sector of three-dimensional Ho\v{r}ava gravity. It is shown that black hole solutions with anti-de Sitter asymptotics are admissible only in the sector of the theory in which the scalar degree of freedom propagates infinitely fast. We derive the most general class of stationary, circularly symmetric, asymptotically anti-de Sitter black hole solutions. We also show that the theory admits black hole solutions with de Sitter and flat asymptotics, unlike three-dimensional general relativity. For all these cases, universal horizons may or may not exist depending on the choice of parameters. Solutions with de Sitter asymptotics can have universal horizons that lie beyond the de Sitter horizon.