Related papers: Newtonian versus black-hole scattering
A spherically symmetric wormhole in Newtonian gravitation in curved space, enhanced with a connection between the mass density and the Ricci scalar, is presented. The wormhole, consisting of two connected asymptotically flat regions,…
Quantum black holes are difficult to describe. We consider two seemingly divergent approaches, high-energy scattering and the proposal to regard black holes as Bose-Einstein condensates of gravitons, and establish a connection between them.…
We initiate a general investigation into gravitational wave signatures of modifications to scattering of gravitational radiation from black holes. Such modifications may be present due to the quantum dynamics that makes black holes…
We explore the possibility of the acoustic analogue of a super-radiance like phenomenon, i.e., the amplification of a sound wave by reflection from the ergo-region of a rotating acoustic black hole in the fluid draining bathtub model in the…
Rotating black holes are well known to amplify the perturbing bosonic fields in certain parameter spaces. This phenomenon is popularly known as superradiance. In addition to rotation in the spacetime, charge plays a crucial role in the…
Belenchia et al. [Phys. Rev. D 98, 126009 (2018)] have analyzed a gedankenexperiment where two observers, Alice and Bob, attempt to communicate via superluminal signals using a superposition of massive particles dressed by Newtonian fields…
We develop an effective theory which describes black holes with quantum mechanical horizons that is valid at scales long compared to the Schwarzschild radius but short compared to the lifetime of the black hole. Our formalism allows one to…
The scattering process of a dynamic perturbation impinging on a draining-tub model of an acoustic black hole is numerically solved in the time domain. Analogies with real black holes of General Relativity are explored by using recently…
Grey-body factors are not only essential ingredients for computing the intensity of Hawking radiation, but also serve as characteristics of black hole's geometry that are closely related to their quasinormal modes. Importantly, they tend to…
We present the wave equation for a minimally coupled scalar field in the background of a rotating four-dimensional black hole that is parametrized by its mass, angular momentum, and four independent U(1) charges. The near horizon structure…
We describe the quantum mechanical scattering of slowly moving maximally charged black holes. Our technique is to develop a canonical quantization procedure on the parameter space of possible static classical solutions. With this, we…
We analyse the classical configurations of a bootstrapped Newtonian potential generated by homogeneous spherically symmetric sources in terms of a quantum coherent state. We first compute how the mass and mean wavelength of these solutions…
Nuclear Compton scattering in the $\Delta$-resonance region is reconsidered within the framework of the $\Delta$-hole model. The different role of the resonant and non-resonant contributions to the transition amplitudes is discussed and…
We study the spectra generated as a result of bulk Comptonization by relativistic electrons in radial flows onto compact objects. We solve numerically the general-relativistic radiative transfer equation in the Schwarzschild spacetime, in…
We consider the effects of gravitons in the collapse of baryonic matter that forms a black hole. We first note that the effective number of (soft off-shell) gravitons that account for the (negative) Newtonian potential energy generated by…
It is argued that the surface radius of a compact source can not be less than its gravitational radius due to the strong gravitational time dilation effects. The such "topological" difference between the Newtonian and relativistic gravity…
We consider non-commutating Simpson-Visser spacetime and study the superradiance phenomena and the shadow cast by the back hole associated with this modified spacetime. We extensively study the different aspects of the black hole associated…
Several properties of canonical quantum gravity modify space-time structures, sometimes to the degree that no effective line elements exist to describe the geometry. An analysis of solutions, for instance in the context of black holes, then…
Obtaining black hole solutions in alternative theories of gravity can be a difficult task due to cumbersome field equations that arise in many of such theories. In order to study the strong field regime in a model-free approach, one can…
The Bekenstein-Hawking formula relates the black hole entropy and horizon area. Semiclassical entropy computations have relied on an action principle that fixes a gauge dependent and classically unobservable boundary three-geometry and…