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arXiv · 1912.05154

Shadow cast and deflection of light by charged rotating regular black holes

Rahul Kumar·Sushant G. Ghosh·Anzhong Wang
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Abstract

We discuss the horizon properties, shadow cast, and the weak gravitational lensing of charged rotating regular black holes, which in addition to mass ($M$) and rotation parameter ($a$) have an electric charge ($Q$) and magnetic charge ($g$). The considered regular black holes are the generalization of the Kerr ($Q=g=0$) and Kerr-Newman ($g=0$) black holes. Interestingly, for a given parameter set, the apparent size of the shadow monotonically decreases and the shadow gets more distorted with increasing charge parameter $Q$. We put constraints on the black hole parameters with the aid of recent M87* shadow observation. The conserved quantities associated with the rotating regular black holes are calculated and also a brief description of the weak gravitational lensing using the Gauss-Bonnet theorem is presented. Interestingly, the deflection angle decreases with the charge of the black hole. Our results \textit{vis-\`{a}-vis} go over to the Kerr and Kerr-Newman black holes in the appropriate limits.

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Rahul Kumar, Sushant G. Ghosh, Anzhong Wang. 2019-12-11. Shadow cast and deflection of light by charged rotating regular black holes. https://doi.org/10.1103/physrevd.100.124024

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