Rotating tensor-multiscalar black holes with two scalars

TL;DR

This paper constructs and analyzes rotating black hole solutions with scalar hair in tensor-multi-scalar theories of gravity, exploring their properties and the influence of target-space curvature.

Contribution

It introduces new rotating black hole solutions with scalar hair in tensor-multi-scalar theories, analyzing their domain of existence and geometric properties.

Findings

Existence of hairy rotating black holes in five different theories.

Variation of solutions with target-space curvature.

Characterization of horizon area and deformation factors.

Abstract

We construct hairy black hole solutions in a particular set of tensor-multi-scalar theories of gravity for which the target-space admits a Killing vector field with periodic flow that is furthermore the generator of a one-parameter family of point transformations which leave the whole theory invariant. As for black holes with scalar hair in general relativity, these must be rotating objects as the scalarization arises from superradiant instability. We analyze the most fundamental rotating solutions (winding number $m=1$) in five theories which differ from each other by the value of the Gauss curvature of the target-space. The domain of existence of these solutions is investigated, as well as their hairyness, horizon area and deformation factor.