arXiv subjects

Vladimir Epp

Publications and source records attributed to Vladimir Epp.

5 recordsLinked to original sources

arXiv2026

Electromagnetic radiation from a point-like charge in a weak gravitational wave: a Shapiro-delay-motivated approach

We investigate the field of a point-like electric charge freely falling in a gravitational wave. In the presence of a gravitational wave, the initially static Coulomb field of the charge becomes time-dependent and generates corresponding radiation. The gravitational wave is treated as a weak perturbation of the Minkowski metric. The electromagnetic four-potential of the charge is sought as a solution to Maxwell's equations in the gravitational wave metric, to first order in perturbation theory. The potentials of the point charge are found in quadratures throughout the space. To regularize the potentials, an approach motivated by the Shapiro effect for the time delay of radiation in a gravitational field is used. The potentials of the charge in the far zone are calculated explicitly for a monochromatic, arbitrarily polarized gravitational wave. The angular distribution of the electromagnetic radiation induced by the gravitational wave is obtained.

gr-qc↗

arXiv2024

Electromagnetic radiation from a relativistic jet induced by a plane gravitational wave

Electromagnetic radiation of a relativistic gas or plasma jet in the field of a plane gravitational wave is investigated. The gravitational wave is considered as a weak (linearized) field on flat Minkowski spacetime. It is assumed that the relativistic jet has large regions with uncompensated electric charge. The deformation of these areas under the action of a gravitational wave leads to the appearance of electric currents that generate electromagnetic radiation. The angular distribution of the intensity of this radiation is found. Cases are considered when the jet and the gravitational wave move in the same direction or towards each other.

gr-qc↗

arXiv2024

Angular momentum of radiation from ultrarelativistic charge

The angular momentum of radiation from an arbitrarily moving relativistic charge is studied. The angular momentum is presented as the sum of the angular momentum relative to the point where the charge is located at a retarded moment of time and the angular momentum relative to an arbitrary stationary center. In particular, the instantaneous center of curvature of the trajectory is considered as such a center. Explicit expressions for the angular distribution of these components of angular momentum fluxes are obtained and studied. It is shown that the angular momentum of the field relative to the position of the charge is determined only by the properties of the electromagnetic radiation field, and the angular momentum relative to an arbitrarily distant point is the vector product of the displacement of this point and the force corresponding to radiation pressure. It is shown that in the ultrarelativistic limit, the canonical angular momentum of the radiation coincides with the angular momentum following from the symmetrized energy-momentum tensor of the electromagnetic field.

physics.class-ph↗

arXiv2023

The angular momentum of electron radiation in a uniform magnetic field

We study theoretically by means of quantum electrodynamics the vortex radiation of a relativistic electron in a uniform magnetic field. The exact expressions for the probability of emission of a photon with a certain angular momentum are found. The classical asymptotics $\hbar\to 0$ of this probability does not match the angular momentum flux density calculated by the classical method using the symmetrized energy-momentum tensor. Although the flux of angular momentum integrated over the radiation directions is the same in both cases. We found the angular momentum flux of the radiation field using the canonical (not symmetrized) energy-momentum tensor and showed that the flux obtained in this way coincide with the classical limit for the probability of photon emission.

quant-ph↗

arXiv2021

Angular momentum transfered by the field of a moving point charge

The flux of angular momentum of electromagnetic field of an arbitrarily moving point charge is investigated. General equations are obtained for the transfer of angular momentum at arbitrary distance from the charge, and corresponding equations in the far-field approximation. An explicit expression is obtained for the flux of angular momentum in the wave zone in terms of coordinates, velocity, and acceleration of the charge. The torque is calculated, that would act on an object if it absorbed all the radiation incident on it. It is shown that this torque is proportional to the curl of the stress tensor of the electromagnetic field; in the far field approximation the torque is proportional to the curl of the Poynting vector.

physics.class-ph↗