Physical Analysis of Black Holes Through Well-Known Approaches

Abstract

This thesis includes the study of thermodynamic geometry, thermal corrections, Joule Thomson expansion, shadow images, quasinormal modes, greybody factors, evaporation of various black holes in non-massive and massive gravities. Ruppeiner approach is investigated for anti de Sitter black hole in Einstein-Maxwell-scalars theory by developing particular forms of the line element of thermodynamic geometry in different phase spaces. It is found that the curvatures in different phase spaces are identical and positive which lead to the repulsive interacting information between black hole molecules. We investigate the thermal stability of anti de Sitter black hole in Einstein-Maxwell-scalar theory and regularized Lovelock theory in the presence of thermal fluctuations. It is observed that momentum relaxation parameter and coupling constants of Lovelock theory increase the thermal stability of black holes. For black hole in regularized Lovelock theory, Joule Thomson expansion is also investigated to obtain some interesting outcomes. The influence of the first-order correction of entropy caused by thermal quantum fluctuations on the thermodynamics of logarithmic corrected charged black hole in massive gravity is discussed. For this purpose, the thermodynamic quantities such as entropy, Helmholtz free energy, internal energy, enthalpy, Gibbs free energy and specific heat are explored. We discuss the influence of the topology of the event horizon, dimensions and non-linearity parameter on the local and global stability of black hole. The higher order generalized uncertainty principle on the thermodynamics of 5- dimensional black hole in Einstein-Gauss-Bonnet gravity coupled to nonlinear electrodynamics is analyzed and compare our results with usual thermodynamic relations. In this framework, we detect the relationship of shadow radius and quasinormal modes. We also verify the inverse relation between the quasinormal modes frequencies and shadow radius, i.e., quasinormal modes should increase with the increasing values of Gauss-Bonnet parameter and electric charge. The new effective approach is adopted to analyze the thermodynamic phase transitions onto non-minimal magnetic charged regular back hole and regular black hole with cosmological constant. We find out the phase transitions points and horizon radii of non-physical range for black holes. The new thermodynamically relations are used to briefly study Joule Thomson affects on regular black holes. The study of greybody factor helps us to understand the quantum nature of black hole. Gravitational potentials and bounds on the greybody factors for some well-known black holes are developed to investigate the influence of Born-Infeld and massive gravity parameters on them. We also discuss the relationship of transmission probability and reflection probability. Finally, we study the Hawking evaporation process, thermodynamics and shadow images in the presence of deflection images of the exact black hole with nonlinear electrodynamics for positive and negative coupling constant  . We observe that evaporation rate depends on  and black hole evaporates more quickly for positive  as compared to negative . For the case = −1, the black hole's lifetime becomes infinite which makes the black hole a remnant and the third law of black hole thermodynamics holds in this scenario. For this black hole, we discuss the thermodynamic quantities and shadow images in the presence of deflection angle. Moreover, we consider the Gibbs energy optical dependence to investigate the Hawking-Page transition. Our findings show that the large and small phase transitions of black hole occur at a specific value of the deflection angle.