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arXiv · 1702.03502

Stable black holes in shift-symmetric Horndeski theories

Daria A. Tretyakova·Kazufumi Takahashi
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Abstract

In shift-symmetric Horndeski theories, a static and spherically symmetric black hole can support linearly time-dependent scalar hair. However, it was shown that such a solution generically suffers from ghost or gradient instability in the vicinity of the horizon. In the present paper, we explore the possibility to avoid the instability, and present a new example of theory and its black hole solution with a linearly time-dependent scalar configuration. We also discuss the stability of solutions with static scalar hair for a special case where nonminimal derivative coupling to the Einstein tensor appears.

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Daria A. Tretyakova, Kazufumi Takahashi. 2017-08-21. Stable black holes in shift-symmetric Horndeski theories. https://doi.org/10.1088/1361-6382%2Faa8057

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