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arXiv · 2104.06583

Rotating scalarized black holes in scalar couplings to two topological terms

De-Cheng Zou·Yun Soo Myung
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Abstract

The tachyonic instability of the Kerr black holes is analyzed in the Einstein-scalar theory with the quadratic scalar couplings to two topological terms which are parity-even Gauss-Bonnet and parity-odd Chern-Simons terms. For positive coupling $α$, we use the (2+1)-dimensional hyperboloidal foliation method to derive the threshold curve which is the boundary between stable and unstable Kerr black holes by considering a spherically symmetric scalar-mode perturbation. In case of negative coupling, a newly bound of $a\ge0.26$ with $a$ the rotation parameter is found for unstable Kerr black holes and its threshold curve is derived.

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De-Cheng Zou, Yun Soo Myung. 2021-07-21. Rotating scalarized black holes in scalar couplings to two topological terms. https://doi.org/10.1016/j.physletb.2021.136545

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