No Scalar-Haired Cauchy Horizon Theorem in Einstein-Maxwell-Horndeski Theories
arXiv:2101.10116 · doi:10.1016/j.physletb.2022.137107
Abstract
Recently, a no inner (Cauchy) horizon theorem for static black holes with non-trivial scalar hairs has been proved in Einstein-Maxwell-scalar theories. In this paper, we extend the theorem to the static black holes in Einstein-Maxwell-Horndeski theories. We study the black hole interior geometry for some exact solutions and find that the spacetime has a (space-like) curvature singularity where the black hole mass gets an extremum and the Hawking temperature vanishes. We discuss further extensions of the theorem, including general Horndeski theories from disformal transformations.
More readable plots, Clarifications on Einstein coupling gamma, Added appendix on regularity condition at the horizons, Added footnote and reference, Typos corrected, 15 pages, 2 figures, Accepted in PLB