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Using the Ernst formalism, a novel solution of vacuum general relativity (GR) was recently obtained [1], describing a Schwarzschild black hole (BH) immersed in a nonasymptotically flat rotating background, dubbed swirling universe, with the…

General Relativity and Quantum Cosmology · Physics 2025-07-30 Zeus S. Moreira , Carlos A. R. Herdeiro , Luís C. B. Crispino

From any location outside the event horizon of a black hole there are an infinite number of trajectories for light to an observer. Each of these paths differ in the number of orbits revolved around the black hole and in their proximity to…

General Relativity and Quantum Cosmology · Physics 2021-07-12 Albert Sneppen

The theory of nonlinear diffraction of intensive light beams propagating through photorefractive media is developed. Diffraction occurs on a reflecting wire embedded in the nonlinear medium at relatively small angle with respect to the…

Pattern Formation and Solitons · Physics 2009-11-13 E. G. Khamis , A. Gammal , G. A. El , Yu. G. Gladush , A. M. Kamchatnov

We study the linear polarization from the accretion disk around weakly and strongly naked Janis-Newman-Winicour singularities. We consider an analytical toy model of thin magnetized fluid ring orbiting in the equatorial plane and emitting…

General Relativity and Quantum Cosmology · Physics 2023-03-28 Valentin Deliyski , Galin Gyulchev , Petya Nedkova , Stoytcho Yazadjiev

We consider the Heisenberg-Euler action for an electromagnetic field in vacuum, which includes quantum corrections to the Maxwell equations induced by photon-photon scattering. We show that, in some configurations, the plane monochromatic…

Optics · Physics 2017-11-02 Fabio Briscese

Regarding axion electrodynamics in the background flat FRW universe, we show that cosmological birefringence arises from an adiabatic noncyclic geometric phase that appears in the quantum state of photons because of their interaction with…

General Relativity and Quantum Cosmology · Physics 2019-08-19 Mansoureh Hoseini , Mohammad Mehrafarin

In this paper, the axion contribution to the electromagnetic wave propagation is studied. First we show how the axion electrodynamics model can be embedded into a premetric formalism of Maxwell electrodynamics. In this formalism, the axion…

High Energy Physics - Theory · Physics 2013-03-08 Yakov Itin

The propagation length of high-energy photons through the Universe is limited by $e^+e^-$ pair production on the extragalactic background radiation. Previous studies reported discrepancies between predicted and observed attenuation,…

High Energy Astrophysical Phenomena · Physics 2021-03-31 Sergey Troitsky

For ultrashort pulses having different states of polarization, the experienced time delay when passing through small apertures is different. In the case of a small slit (or a circular aperture), we report a significantly stronger dispersion…

We study the effect of light-bending on the signal of a pulsar in binaries with rotating black hole companions, focusing on stellar mass black holes. We show that the impacts of various parameters on the bending delays visually match with…

General Relativity and Quantum Cosmology · Physics 2025-06-09 Jyotijwal Debnath , Manjari Bagchi

Optical properties of a one-dimensional photonic structure consisting of Kerr-type nonlinear and magnetic layers under the action of an external static magnetic field in the Faraday geometry are investigated. The structure is a periodic…

We study polarization dependent photon propagation in static, spherically symmetric spacetimes permeated by strong magnetic fields, with the aim of quantifying how finite emission and detection radii modify vacuum birefringence signals.…

General Relativity and Quantum Cosmology · Physics 2026-01-21 Ali Övgün , Reggie C. Pantig

Nonlinear waves emitted from a moving source are studied. A meandering spiral in a reaction-diffusion medium provides an example, where waves originate from a source exhibiting a back-and-forth movement in radial direction. The periodic…

Statistical Mechanics · Physics 2007-05-23 Lutz Brusch , Alessandro Torcini , Markus Baer

Non dispersive electronic Rydberg wave packets may be created in atoms illuminated by a microwave field of circular polarization. We discuss the spontaneous emission from such states and show that the elastic incoherent component (occuring…

Quantum Physics · Physics 2009-10-31 Dominique Delande , Jakub Zakrzewski

This research delves into the optical characteristics of stationary, spherically symmetric black holes. These black holes follow the Konoplya-Zhidenko deformation rule in arbitrary gravity theories. This research finds that the effects of…

General Relativity and Quantum Cosmology · Physics 2025-05-28 Qiao Yue , Zhaoyi Xu , Meirong Tang

We give simple and general explanation to the effect of unbound acceleration of particles by black holes. It is related to the fact that the scalar product of a timelike vector of the four-velocity of an ingoing particle and the lightlike…

General Relativity and Quantum Cosmology · Physics 2011-04-20 Oleg B. Zaslavskii

Modeling the late inspiral and merger of supermassive black holes is central to understanding accretion processes and the conditions under which electromagnetic emission accompanies gravitational waves. We use fully general relativistic,…

General Relativity and Quantum Cosmology · Physics 2015-05-27 Tanja Bode , Tamara Bogdanovic , Roland Haas , James Healy , Pablo Laguna , Deirdre Shoemaker

Some BL Lacertae objects show a periodic behaviour in their light curves that is often attributed to the orbital motion of a central binary black hole system. On this basis, and assuming a circular orbit, Rieger and Mannheim have recently…

Astrophysics · Physics 2009-11-07 F. De Paolis , G. Ingrosso , A. A. Nucita

Excitons in a semiconductor monolayer form a collective resonance that can reflect resonant light with extraordinarily high efficiency. Here, we investigate the nonlinear optical properties of such atomistically thin mirrors and show that…

Mesoscale and Nanoscale Physics · Physics 2022-03-02 Valentin Walther , Lida Zhang , Susanne F. Yelin , Thomas Pohl

Static black holes contain regions of spacetime which not even light can escape from. In the centre of mass frame, these blocks are separated from each other by event horizons. Unlike pointlike particles, fields can spread and interact…

Analysis of PDEs · Mathematics 2024-12-03 Antti Kujanpää