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arXiv · 2604.11357

Charged Black Holes in KR-gravity Surrounded by Perfect Fluid Dark Matter

Faizuddin Ahmed·Mohsen Fathi·Edilberto O. Silva
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Abstract

In this work, we systematically investigate the null geodesics of electrically charged black holes in a gravitational framework that incorporates Lorentz violation induced by a background Kalb-Ramond (KR) field, in the presence of perfect-fluid dark matter. The properties of the photon sphere, black hole shadow, and photon trajectories are analyzed in detail. Furthermore, to explore the combined effects of Lorentz violation and dark matter on the motion of neutral test particles, we examine the innermost stable circular orbit (ISCO) in this spacetime. In addition, the epicyclic frequencies of test particles are studied to gain further insight into the dynamical behavior of particle motion around these black holes. The main analytical results are complemented by a phenomenological QPO analysis, a thermodynamic investigation, and a discussion of the sparsity of Hawking radiation, allowing us to connect optical, dynamical, and thermodynamic signatures within a single framework.

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Faizuddin Ahmed, Mohsen Fathi, Edilberto O. Silva. 2026-04-13. Charged Black Holes in KR-gravity Surrounded by Perfect Fluid Dark Matter. https://arxiv.org/abs/2604.11357

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