Related papers: Observable form of pulses emitted from relativisti…
This paper presents an analysis of the radiation seen by an observer in circular acceleration, for a magnetic spin. This is applied to an electron in a storage ring, and the subtilty of the interaction of the spin with the spatial motion of…
We model the light-curves from radiation-driven clouds near an accreting black hole. Taking into account the multiple images due to strong gravitational lensing, we find that sharp spikes can significantly enhance the observed flux.…
Fast radio bursts (FRBs) are extragalactic radio transients with millisecond duration and extremely high brightness temperature. Very recently, some highly circularly polarized bursts were found in a repeater, FRB 20201124A. The significant…
A derivation of the properties of pulsed radiative imaging systems is presented with examples drawn from conventional, synthetic aperture, and interferometric radar. A geometric construction of the space and time components of a radar…
Frequency-dependent gravitational lens effects are found for trajectories of electromagnetic rays passing through a distribution of plasma near a massive object. Ray propagation through plasma adds extra terms to the equations of motion…
In the previous work, we investigated the rotation curves of galaxies assuming that the dark matter consists of ultra light boson appearing in $'$late time phase transition' theory. Generalizing this work, we consider the effect of visible…
A strong light pulse propagating in a nonlinear medium causes an effective change in the local refractive index. With a suitable tuning of the pulse velocity, the leading and trailing edge of the pulse were predicted to behave as analogue…
We investigate the influence of plasma presence on relativistic images formed by Schwarzschild black hole lensing. When a gravitating body is surrounded by a plasma, the lensing angle depends on a frequency of the electromagnetic wave due…
A novel imaging principle based on the interaction of electromagnetic waves with a beam of relativistic electrons is proposed. Wave-particle interaction is assumed to take place in a small spatial domain, so that each electron is only…
The radiative mechanism of coherent radio emission has remained an enigma since the discovery of pulsars, even the emergence of fast radio bursts (FRBs), which exhibit similarities to the single-pulse behavior of pulsars and have opened a…
We report an experimental-computational study of the optical properties of plasma mirrors (PMs) at the incident laser frequency when irradiated directly at relativistic intensity (1e18 < I_0 < 1e19 W/cm^2) by near-normally incident (4…
We study the emission of space-time waves produced by back-reaction effects during a collapse of a spherically symmetric universe with a time dependent cosmological parameter, which is driven by a scalar field. As in a previous work the…
The effects of the de Broglie-Bohm quantum potential on a test particle of mass $m$ are investigated in a conformally-flat geometry. A real, nonlinear, scalar field $\Psi$ is introduced and related directly to the conformal factor and to…
The strange visual appearance of objects is one of the puzzling predictions of Einstein's relativity. This is mainly due to the distinction between measuring and seeing, where the former is described by the Lorentz Transformation and the…
Radiation reaction is revisited, first in a new classical aproach, where the physical particle 4-momentum is redefined as the energy-momentum flux across the future light cone and is not parallel to the 4-velocity. Then in a semi-classical…
The spectra of Compton radiation emitted during electron scattering off an intense laser beam are calculated using the framework of strong-field quantum electrodynamics. We model these intense laser beams as finite length plane-wave-fronted…
The scattering of relativistic Dirac particles by a Coulomb field $\pm Ze^2/r$ in two dimensions is studied and the scattering amplitude is obtained as a partial wave series. For small $Z$ the series can be summed up approximately to give a…
In the relativistic plasma surrounding a pulsar, a subluminal ordinary-mode electromagnetic wave will propagate along a magnetic field line. After some distance, it can break free of the field line and escape the magnetosphere to reach an…
The question is examined of a mirror which starts from rest and either (i) accelerates for some time and eventually reverts to motion at constant velocity, or (ii) continues accelerating forever. A sharp distinction is made between cases…
The adiabatic invariance of the magnetic moment during particle motion is of fundamental importance to the dynamics of magnetized plasma. The related rate of pitch angle scattering is investigated here for fast particles that thermally…