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arXiv · 2203.07298

Violation of bound on chaos for charged probe in Kerr-Newman-AdS black hole

Bogeun Gwak·Naoto Kan·Bum-Hoon Lee·Hocheol Lee
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Abstract

We investigate the conjectured bound on the Lyapunov exponent for a charged particle with angular motion in the Kerr-Newman-AdS black hole. The Lyapunov exponent is calculated based on the effective Lagrangian. We show that the negative cosmological constant reduces the chaotic behavior of the particle, namely, it decreases the Lyapunov exponent. Hence, the bound is more effective in the AdS spacetime than in the flat spacetime. Nevertheless, we find that the bound can be violated when the angular momenta of the black hole are turned on. Moreover, we show that in an extremal black hole, the bound is more easily violated compared to the nonextremal black hole.

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Bogeun Gwak, Naoto Kan, Bum-Hoon Lee, Hocheol Lee. 2022-03-14. Violation of bound on chaos for charged probe in Kerr-Newman-AdS black hole. https://doi.org/10.1007/jhep09(2022)026

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