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arXiv · 2303.01956

Black hole shadow and chaos bound violation in $f(T)$ teleparallel gravity

Andrea Addazi·Salvatore Capozziello
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Abstract

We show that the so-called chaos bound, proposed by Maldacena, Shenker, and Stanford, can be violated in $f(T)$ teleparallel gravity. In particular, it is possible to select a new gravitational Lyapunov parameter, controlling chaotization of circular trajectories, in black hole photo-sphere, that can exceed the Maldacena, Shenker and Stanford thermal bound. This feature alters the standard quasi-normal modes and ringdown phase after black hole merging with intriguing implications for future gravitational wave detections and black hole shadow measurements. It is a general characteristic for several gravitational theories beyond standard General Relativity.

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Andrea Addazi, Salvatore Capozziello. 2023-03-03. Black hole shadow and chaos bound violation in $f(T)$ teleparallel gravity. https://doi.org/10.1016/j.physletb.2023.137828

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