Related papers: Superradiance without event horizons in General Re…
Rotating black holes can form dense boson clouds through superradiant instability, making Kerr black holes a powerful probe of ultralight massive bosons. Previous studies of black hole superradiance have often treated bosonic fields…
The observation of electromagnetic radiation emitted or absorbed by matter was instrumental in revealing the quantum properties of atoms and molecules in the early XX century, and constituted a turning-point in the development of the…
This thesis explores two avenues into understanding the physics of black holes and horizons beyond general relativity, via analogue models and Lorentz violating theories. Analogue spacetimes have wildly different dynamics to general…
We argue that, classically, $s$-wave electrons incident on a magnetically charged black hole are swallowed with probability one: the reflection coefficient vanishes. However, quantum effects can lead to both electromagnetic and…
We present a comprehensive analysis of super-Eddington black hole accretion simulations that solve the GRMHD equations coupled with angle-discretized radiation transport. The simulations span a range of accretion rates, two black hole…
We numerically investigate the superradiant amplification effect of a charged scalar filed in the scattering experiment and the black hole bomb model in a charged black-bounce spacetime. Due to the shallowing effect on the effective…
Hawking radiation is nowadays being understood as tunnelling through black hole horizons. Here, the extension of the Hamilton-Jacobi approach to tunnelling for non-rotating and rotating black holes in different non-singular coordinate…
We consider a very simple model for gravitational wave echoes from black hole merger ringdowns which may arise from local Lorentz symmetry violations that modify graviton dispersion relations. If the corrections are sufficiently soft so…
The No Hair theorem in classical general relativity predicts that rotating black holes are specified by the Kerr metric, which is uniquely identified by the mass and spin. However, as a pioneering study beyond general relativity, the…
We analyze the flow of energy and entropy emitted by a class of moving mirror trajectories which provide models for the radiation fields produced by black hole evaporation. The mirror radiation fields provide natural, concrete examples of…
This study explores spherically symmetric non-linear electrodynamics black holes and their effects on light propagation. We derive the governing metric, revealing radial coordinate dynamics within the event horizon. We analyze photon…
The isolated black hole radiation of both Hawking and Zel'dovich are idealized abstractions as there is always another body to distort the potential. This is considered with respect to both gravitational tunneling, and black hole "no-hair"…
Hawking radiation from a black hole can be viewed as quantum tunneling of particles through the event horizon. Using this approach we provide a general framework for studying corrections to the entropy of black holes beyond semiclassical…
In 2016, the Nottingham group detected the rotational superradiance effect. While this experiment demonstrated the robustness of the superradiance process, it still lacks a complete theoretical description due to the many effects at stage…
We investigate the high and low energy scattering of charged scalar waves from an extreme dilaton black hole (DBH). The analyses here correspond to forward scattering processes of two charged scalar particles with dilaton coupling under a…
We continue a study by Adler and Ramazano\uglu (AR) of "black" holes as modified by a scale invariant dark energy action. For the spherically symmetric Schwarzschild-like case, (AR) found that there is no event horizon; hence spacetime is…
Black holes provide a natural laboratory to study particle physics and astrophysics. When black holes are surrounded by matter fields, there will be plenty of phenomena which can have observational consequences, from which we can learn…
Extending researches on Hawking radiation to conformal gravity theory, we discuss Hawking radiation of different particles across charged rotating AdS black holes in conformal gravity, including charged massive particles, complex scalar and…
The absorption and emission spectra for the minimally-coupled brane and bulk scalar fields are numerically computed when the spacetime is a $5d$ rotating black hole carrying the two different angular momentum parameters $a$ and $b$. The…
Although gravitational waves tend to erase eccentricity of an inspiraling binary system, ellipticity can be generated in the presence of surrounding matter. We present a semi-analytical method for understanding the eccentricity distribution…