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arXiv · 2309.06454

Photonsphere, shadow, quasinormal modes, and greybody bounds of non-rotating Simpson-Visser black hole

Sohan Kumar Jha
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Abstract

In this manuscript, we study photonsphere, shadow, quasinormal modes, Hawking temperature, and greybody bounds of a non-rotating Simpson-Visser black hole which is a regular black hole. We observe that though the radius of the photonsphere does depend on the Simpson-Visser parameter $\alpha$, the shadow radius is independent of it. The shadow radius is found to be equal to that for Schwarzschild black hole. We, then, study quasinormal frequencies of the Simpson-Visser black hole for scalar and electromagnetic perturbations with the help of $6$th order WKB method. We tabulate values of quasinormal frequencies for various values of $\alpha$, angular momentum $\ell$, and overtone number $n$. We also graphically show the dependence of real and imaginary parts of quasinormal frequency on $\alpha$ and $\ell$. Additionally, We study the convergence of the WKB method for various values of pair $(n,\ell)$. Finally, we shed light on the dependence of the Hawking temperature on the parameter $\alpha$ and the dependence of greybody bounds on $\alpha$ and $\ell$.

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Sohan Kumar Jha. 2023-09-12. Photonsphere, shadow, quasinormal modes, and greybody bounds of non-rotating Simpson-Visser black hole. https://doi.org/10.1140/epjp%2Fs13360-023-04384-5

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