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arXiv · 1104.3180

Instability of rotating black hole in a limited form of $f(R)$ gravity

Yun Soo Myung
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Abstract

We investigate the stability of $f(R)$-rotating (Kerr) black hole obtained from a limited form of $f(R)$ gravity. In order to avoid the difficulty of handling fourth order linearized equations, we transform this form of $f(R)$ gravity into the scalar-tensor theory by introducing two auxiliary scalars. In this case, the linearized curvature scalar equation leads to a massive scalaron equation. It turns out that the $f(R)$-rotating black hole is unstable because of the superradiant instability known as the black-hole bomb idea.

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Yun Soo Myung. 2011-06-28. Instability of rotating black hole in a limited form of $f(R)$ gravity. https://doi.org/10.1103/physrevd.84.024048

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