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arXiv · 2103.17021

Study of Einstein-bumblebee gravity with Kerr-Sen-like solution in the presence of a dispersive medium

Abstract

A Kerr-Sen-like black hole solution appears in the Einstein-bumblebee theory of gravity. The solution contains contains a Lorentz violating parameter in an explicit manner. We study the null geodesics in the background of this Kerr-Sen-like black hole surrounded by a dispersive medium like plasma. We investigate the effect of the charge of the black hole, the Lorentz violation parameter, and the plasma parameter on the photon orbits with the evaluation of the effective potential in the presence of both the Lorentz violation parameter and the plasma parameter. We also study the influence of the Lorentz violation parameter and plasma parameter on the emission of energy from the black hole due to thermal radiation. Besides, we compute the angle of deflection of massless particles with weak-field approximation in this generalized situation and examine how it varies with the Lorentz violation parameter in presence of plasma. Constraining the parameters of this Lorentz violating Kerr-Sen-like black hole is also attempted here with the result obtained from the observations of the Event Horizon Telescope (EHT) collaboration.

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Sohan Kumar Jha, Sahazada Aziz, Anisur Rahaman. 2021-03-31. Study of Einstein-bumblebee gravity with Kerr-Sen-like solution in the presence of a dispersive medium. https://doi.org/10.1140/epjc%2Fs10052-022-10042-4

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