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arXiv · 2509.02728

Saturation of Chaos Bound in a Phenomenological Rotating Black Hole--Effective Matter System at Low-Temperature Limit

Abstract

We study the chaotic behavior of a phenomenological system of rotating black holes (BHs) surrounded by radiation, dust, and dark matter as effective matter fluids. We show that the chaos bound is saturated -- but never violated -- when the density parameter $k \rightarrow 1$, which corresponds to a high dark matter concentration in the halo. This saturation is independent of radiation and dust density, occurring in the low-temperature regime where the BH's surface gravity and Hawking temperature decrease. Our results suggest that rotating BHs subjected to a phenomenological representation of a more realistic matter environment can scramble information as efficiently as allowed by physical laws in this limit. This work links quantum chaos research with phenomenological BH-matter configurations, providing a motivation for studies of chaos in astrophysical BHs.

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Reza Pourkhodabakhshi. 2025-09-02. Saturation of Chaos Bound in a Phenomenological Rotating Black Hole--Effective Matter System at Low-Temperature Limit. https://doi.org/10.1103/d2b7-t7y7

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