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arXiv · 2009.03904

Spin-induced scalarized black holes

Carlos A. R. Herdeiro·Eugen Radu·Hector O. Silva·Thomas P. Sotiriou·Nicolás Yunes
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Abstract

It was recently shown that a scalar field suitably coupled to the Gauss-Bonnet invariant $\mathcal{G}$ can undergo a spin-induced linear tachyonic instability near a Kerr black hole. This instability appears only once the dimensionless spin $j$ is sufficiently large, that is, $j \gtrsim 0.5$. A tachyonic instability is the hallmark of spontaneous scalarization. Focusing, for illustrative purposes, on a class of theories that do exhibit this instability, we show that stationary, rotating black hole solutions do indeed have scalar hair once the spin-induced instability threshold is exceeded, while black holes that lie below the threshold are described by the Kerr solution. Our results provide strong support for spin-induced black hole scalarization.

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Carlos A. R. Herdeiro, Eugen Radu, Hector O. Silva, Thomas P. Sotiriou, Nicolás Yunes. 2020-09-08. Spin-induced scalarized black holes. https://doi.org/10.1103/physrevlett.126.011103

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