Shadow thermodynamics of non-linear charged Anti-de Sitter black holes

Abstract

Non-linear interaction between the electromagnetic fields (EMF) are occurred when vacuum polarization in quantum electrodynamics (QED) happens. The field of non-linear electrodynamics which may be resulting from this interaction could have important effects on black hole physics. In this work, we investigate the relationship between the observable quantity, the shadow radius and the first-order phase transition for the non-linear charged AdS black hole in the frame of the Einstein-power-Yang-Mills (EPYM) gravity. Through the analysis, we find with a certain condition there exist the non-monotonic behaviors between the shadow radius, the horizon radius, and temperature (or pressure). And from the viewpoint of the shadow radius, the phase transition temperature is higher than that from the viewpoint of the horizon radius with the same condition. These indicate that the shadow radius can be regarded a probe to reveal the thermodynamic phase transition information of black holes. When the system is undergoing the phase transition in two cases of the different non-linear YM charge parameter values: γ = 1, 1.5, the thermal profiles of the coexistent big and small black hole phases with the temperature are presented. Furthermore, the effects of non-linear YM charge parameter on the shadow radius and the thermal profile are also investigated.

Greybody factors of bosons and fermions emitted from higher dimensional dS/AdS black holes in Einstein-bumblebee gravity theory

“…and by considering a mathematical constraint f (r 0 ) ≈ 1 for a static observer located at a special location (see for example [86,87] in which the appropriate normalization for the time-like Killing vector was applied), we can write the shadow radius [88] as follows…”