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

TL;DR

This paper analyzes the optical, dynamical, and thermodynamic properties of charged black holes in KR-gravity with perfect fluid dark matter, focusing on photon trajectories, ISCO, and Hawking radiation.

Contribution

It provides a comprehensive study of how Lorentz violation and dark matter influence black hole shadows, particle orbits, and thermodynamic behavior in a unified framework.

Findings

Photon sphere and shadow properties are significantly affected by dark matter and Lorentz violation.

The ISCO and epicyclic frequencies reveal modifications in particle stability and oscillations.

Hawking radiation sparsity and thermodynamics are altered by the combined effects studied.

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.