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arXiv · 1510.07400

Instability of hairy black holes in shift-symmetric Horndeski theories

Hiromu Ogawa·Tsutomu Kobayashi·Teruaki Suyama
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Abstract

Recently it was pointed out that in shift-symmetric scalar-tensor theories a black hole can have nontrivial scalar hair which depends linearly on time. We develop black hole perturbation theory for such solutions and compute the quadratic action of odd-parity perturbations. We show that around all the solutions known so far with such time-dependent scalar hair the perturbations trigger instabilities or are presumably strongly coupled.

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Hiromu Ogawa, Tsutomu Kobayashi, Teruaki Suyama. 2016-09-11. Instability of hairy black holes in shift-symmetric Horndeski theories. https://doi.org/10.1103/physrevd.93.064078

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