Black holes with surrounding matter in scalar-tensor theories

Abstract

We uncover two mechanisms that can render Kerr black holes unstable in scalar-tensor gravity, both associated to the presence of matter in the vicinity of the black hole and the fact that this introduces an effective mass for the scalar. Our results highlight the importance of understanding the structure of spacetime in realistic, astrophysical black holes in scalar-tensor theories.Comment: 5 pages. Published version. arXiv admin note: substantial text overlap with arXiv:1305.693