Chaotic motion of particle in regular black hole supported by Galactic halo

Aofei Sang; Ziyi Fang

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arXiv · 2603.00999

Chaotic motion of particle in regular black hole supported by Galactic halo

Aofei Sang·Ziyi Fang

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Abstract

We investigate the chaotic dynamics of the massless test particles moving in the regular black hole supported by a Dehnen-type dark matter halo. By limiting the particle within a external harmonic potential, we employ Poincaré sections and Lyapunov exponents as diagnostic tools and analyze the transition from regular to chaotic motion as the halo scale parameter $a$ increase. These findings indicate that the galactic halo acts as a primary driver of chaos in this regular black hole geometry, significantly distorting the phase space structure near the potential center, acting as a primary driver of chaos. Crucially, our results elucidate the distinct imprint of dark matter halos on particle dynamics, suggesting that observing such chaotic signatures in astrophysical systems could provide a novel method for detecting and constraining the properties of dark matter in future observations.

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Aofei Sang, Ziyi Fang. 2026-03-01. Chaotic motion of particle in regular black hole supported by Galactic halo. https://arxiv.org/abs/2603.00999

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