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arXiv · 1503.00126

Time-Dependent Scalar Fields in Modified Gravities in a Stationary Spacetime

Yi Zhong·Bao-Min Gu·Shao-Wen Wei·Yu-Xiao Liu
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Abstract

Most no-hair theorems involve the assumption that the scalar field is independent of time. Recently in [Phys. Rev. D90 (2014) 041501(R)] the existence of time-dependent scalar hair outside a stationary black hole in general relativity was ruled out. We generalize this work to modified gravities and non-minimally coupled scalar field with an additional assumption that the spacetime is axisymmetric. It is shown that in higher-order gravity such as metric $f(R)$ gravity the time-dependent scalar hair doesn't exist. While in Palatini $f(R)$ gravity and non-minimally coupled case the time-dependent scalar hair may exist.

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Yi Zhong, Bao-Min Gu, Shao-Wen Wei, Yu-Xiao Liu. 2016-08-26. Time-Dependent Scalar Fields in Modified Gravities in a Stationary Spacetime. https://doi.org/10.1140/epjc%2Fs10052-016-4225-3

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