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arXiv · 2204.10087

Stable bound orbits around static Einstein-Gauss-Bonnet black holes

Ryotaku Suzuki·Shinya Tomizawa
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Abstract

As is well-known, asymptotically flat, static and spherically symmetric black holes do not admit stable bound orbits of massive/massless particles outside the horizon in higher-dimensional Einstein gravity. However, for massive particles, this dramatically changes in higher curvature theories. We clarify the parameter range such that there exist stable bound orbits in $d$-dimensional Einstein-Gauss-Bonnet theories for $6\leq d\leq 9$. In particular, we show the existence of the lower bound of the Gauss-Bonnet coupling constant below which stable bound orbits cease to exist. Moreover, we also find that for AdS-black holes in the theories, there can exist two stable circular orbits outside the horizon.

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Ryotaku Suzuki, Shinya Tomizawa. 2022-04-21. Stable bound orbits around static Einstein-Gauss-Bonnet black holes. https://doi.org/10.1103/physrevd.105.124033

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