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

TL;DR

This paper investigates the properties of a non-rotating Simpson-Visser black hole, including its photon sphere, shadow, quasinormal modes, Hawking temperature, and greybody bounds, revealing how these features depend on the black hole's parameters.

Contribution

It provides a detailed analysis of the Simpson-Visser black hole's optical and thermodynamic properties, including quasinormal modes and greybody bounds, with new insights into parameter dependencies.

Findings

Shadow radius equals Schwarzschild black hole's shadow.

Quasinormal frequencies depend on the Simpson-Visser parameter $oldsymbol{\alpha}$, angular momentum, and overtone number.

Hawking temperature and greybody bounds vary with $oldsymbol{\alpha}$ and angular momentum.

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 $\ell$.