Related papers: Free-free absorption effects on Eddington luminosi…
We show that collider experiments have the potential to exclude a light scalar field as well as generic models of modified gravity as dark energy candidates. Our mechanism uses the spectrum radiated by black holes and can equally well be…
The coherent interaction between free electrons and optical fields can produce free-electron compression and push the temporal resolution of ultrafast electron microscopy to the attosecond regime. However, a large electron-light interaction…
This paper investigates gravitational lensing effects in the presence of plasma in the strong deflection limit, which corresponds to light rays circling around a compact object and forming higher-order images. While previous studies of this…
An electron-positron atmosphere is inevitably created around a black hole accretion disc, the spectrum of which extends to MeV energies. Pairs created in photon-photon collisions outside the disc are blown away by soft radiation (which…
We theoretically study the effect of THz radiation on the linear optical absorption spectra of semiconductor structures. A general theoretical framework, based on non-equilibrium Green functions, is formulated, and applied to the…
When treating the absorption of light, one focuses on the absorption coefficient, related to the probability of photons to survive while traversing a layer of material. From the point of view of particles doing the absorption, however, the…
Motivated by string theory scenarios, we study the optical aspect of AdS black holes in Einstein-Maxwell-dilaton theory. Concretely, we investigate and examine the shadows and the deflection angle of light rays by such cosmological black…
In this work, we investigate the signatures of black holes within an effective quantum gravity framework recently proposed in the literature [1] . We begin by outlining the general setup, highlighting the two distinct models under…
In this paper, we formulate an analytical expression of greybody factor in the context of rotating Bardeen black hole which is valid in low energy and low angular momentum region. Primarily, we analyze the profile of effective potential…
A relativistic/QED theory of light pressure on electrons by an isotropic, in particular blackbody radiation predicts thermalization rates of free electrons over entire span of energies available in the lab and the nature. The calculations…
At luminosities below a few percent of Eddington, accreting black holes switch to a hard spectral state which is very different from the soft blackbody-like spectral state that is found at higher luminosities. The hard state is…
Motivated by the effect of the energy of moving particles in $C-$metric, we first obtain exact accelerating black hole solutions in gravity's rainbow. Then, we study the effects of gravity's rainbow and $C-$metric parameters on the Ricci…
We study the influence of phantom fields on strong field gravitational lensing. Supposing that the gravitational field of the supermassive central object of the Galaxy is described by a phantom black hole metric, we estimate the numerical…
In models with extra dimensions, a black hole evaporates both in the bulk and on the visible brane, where standard model fields live. The exact emissivities of each particle species are needed to determine how the black hole decay proceeds.…
Electrons at the surface of a plasma that is irradiated by a laser with intensity in excess of $10^{23}~\mathrm{W}\mathrm{cm}^{-2}$ are accelerated so strongly that they emit bursts of synchrotron radiation. Although the combination of high…
Motivated by recent works on light deflection and shadow behaviors on AdS geometries, we investigate the deflection angle of light rays by superentropic black holes. Taking appropriate approximations, we first obtain the involved…
We consider rotating charged black holes with a scalar dilaton field and surrounded by plasma, with the purpose of studying their shadows. The corresponding metric has been previously obtained in the literature from the static solution by…
We study the possibility of identifying dark matter in the galactic center from the physical properties of the electromagnetic radiation emitted from a optical-thin disk region around a static and spherically symmetric black hole. In…
We study very-high rate spherically symmetric accretion flows onto a massive black hole (BH; 10^2 < M_BH < 10^6 Msun) embedded in a dense gas cloud with a low abundance of metals, performing one-dimensional hydrodynamical simulations which…
We find radiation in an infalling frame and present an explicit analytic evidence of the failure of no drama condition by showing that an infalling observer finds an infinite negative energy density at the event horizon. The negative and…