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arXiv · 1903.08312

Black holes in Gauss-Bonnet and Chern-Simons-scalar theory

Yun Soo Myung·De-Cheng Zou
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Abstract

We carry out the stability analysis of the Schwarzschild black hole in Gauss-Bonnet and Chern-Simons-scalar theory. Here, we introduce two quadratic scalar couplings ($\phi_1^2,\phi_2^2$) to Gauss-Bonnet and Chern-Simons terms, where the former term is parity-even, while the latter one is parity-odd. The perturbation equation for the scalar $\phi_1$ is the Klein-Gordon equation with an effective mass, while the perturbation equation for $\phi_2$ is coupled to the parity-odd metric perturbation, providing a system of two coupled equations. It turns out that the Schwarzschild black hole is unstable against $\phi_1$ perturbation, leading to scalarized black holes, while the black hole is stable against $\phi_2$ and metric perturbations, implying no scalarized black holes.

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Yun Soo Myung, De-Cheng Zou. 2019-03-20. Black holes in Gauss-Bonnet and Chern-Simons-scalar theory. https://doi.org/10.1142/s0218271819501141

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