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arXiv · 2207.13114

$D=5$ static, charged black holes, strings and rings with resonant, scalar $Q$-hair

Yves Brihaye·Carlos Herdeiro·Eugen Radu
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Abstract

A mechanism for circumventing the Mayo-Bekenstein no-hair theorem allows endowing four dimensional $(D=4)$ asymptotically flat, spherical, electro-vacuum black holes with a minimally coupled $U(1)$-gauged scalar field profile: $Q$-$hair$. The scalar field must be massive, self-interacting and obey a {\it resonance condition} at the threshold of (charged) superradiance. We establish generality for this mechanism by endowing three different types of static black objects with scalar hair, within a $D=5$ Einstein-Maxwell-gauged scalar field model: asymptotically flat black holes and black rings; and black strings which asymptote to a Kaluza-Klein vacuum. These $D=5$ $Q$-hairy black objects share many of the features of their $D=4$ counterparts. In particular, the scalar field is subject to a resonance condition and possesses a $Q$-ball type potential. For the static black ring, the charged scalar hair can balance it, yielding solutions that are singularity free on and outside the horizon.

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Yves Brihaye, Carlos Herdeiro, Eugen Radu. 2022-07-26. $D=5$ static, charged black holes, strings and rings with resonant, scalar $Q$-hair. https://doi.org/10.1007/jhep10(2022)153

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