Generalized Study of Horizons, Photon Sphere and its Shadows in Rotating Black Holes

Abstract

In this thesis, we considered two static black holes, one in Kalb-Ramond gravity and the other in Bopp–Podolsky Electrodynamics. The metrics of the black holes have been discussed in a nutshell. The radius of photon sphere of both black holes have also been discussed. The photon sphere radius of hairy black hole in Bopp-Podolsky Electrodynamics is further used to study the linear radius of the black hole shadow, angular velocity and Lyapunov exponent. The center of mass energy of two colliding particles is then investigated. We converted the static black holes into rotating black holes by using Newman-Janis algorithm. These rotating metrics are then explored to study horizon structure using the numerical technique. Moreover, we construct the null geodesic equations and effective potential is investigated. In addition, a mathematical scheme is derived from the effective potential for calculating and plotting the shadows. The numerical results obtained for the shadows are used to study the distortion and energy emission rate. We obtained some interesting results and analyzed the effect of black hole parameters on the above mentioned properties. We find that the parameters corresponding to both black holes have a significant effect on the different properties mentioned above, especially, the shadow. Lastly, the parametric constraints are obtained for the black hole in Kalb-Ramond gravity.