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arXiv · 1911.01847

Stealth black holes in shift symmetric kinetic gravity braiding

Reginald Christian Bernardo·John Celestial·Ian Vega
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Abstract

We derive all hairy stealth black holes in the most general second-order, shift symmetric, scalar-tensor theory with luminally propagating gravitational waves, often called kinetic gravity braiding. Our approach exploits an overlooked loophole in a recently obtained no-go statement which claims shift symmetry breaking to be necessary for stealth solutions to exist in kinetic gravity braiding. We highlight the essential role played by a covariantly constant kinetic density in obtaining these solutions. Lastly, we propose a parametrization of the theories based on the asymptotics of its stealth solutions and comment on the intriguing singular effective metric for scalar perturbations in stealth black holes.

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Reginald Christian Bernardo, John Celestial, Ian Vega. 2019-12-18. Stealth black holes in shift symmetric kinetic gravity braiding. https://doi.org/10.1103/physrevd.101.024036

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