相关论文: Radiation from a Superluminal Source
An intervening galaxy acts as a gravitational lens and produces multiple images of a single source such as a remote galaxy. Galaxies have peculiar speeds in addition to the bulk motion arising due to the expansion of the universe. There is…
An exact solution of the Dirac equation in the presence of an arbitrary electromagnetic plane wave is found, which corresponds to a focused electron wave packet, with the focus of the wave packet moving at the speed of light in the opposite…
A charged particle passing through or near a narrow optical fiber induces, by polarisation, coherent light guided by the fiber. In the limit of zero crossing angle, the radiation tends towards a Cherenkov radiation with a discrete spectrum,…
A relativistic electron uniformly rotating along an equatorial orbit around a dielectric ball may generate Cherenkov radiation tens of times more intense as that in case of revolution of a particle in a continuous, infinite and transparent…
It has been shown by Liberati et al. [quant-ph/9904013] that a dielectric medium with a time-dependent refractive index may produce photons. We point out that a free electric charge which interacts with such a medium will emit quantum…
We posit a second massless photon, uncoupled to known forms of matter but undergoing Lorentz non-invariant velocity mixing with ordinary photons. Our speculation within a speculation suffers from the sin of implausibility but enjoys the…
We present a possible solution to the reported OPERA anomaly for the speed of neutrinos, based on the idea that it is a local effect caused by a scalar field sourced by the earth. The coupling of the scalar to neutrinos effectively changes…
We have estimated the reflected component of Cherenkov radiation, which arises in developing of an extensive air shower with primary energy of 10^20 eV over the ocean surface. It has been shown that, under conditions of the TUS experiment,…
We investigate the radiation from a charged particle moving outside a dielectric cylinder parallel to its axis. It is assumed that the cylinder is immersed into a homogeneous medium. The expressions are given for the vector potential and…
We pinpoint how a subatomic particle with non-zero mass may attain, in principle, velocities faster-than-light by travelling in helical motion in the limit of very large momentum. This is an educated guess by virtue of the MINOS and OPERA…
The acceleration of the expansion of the universe has been argued for by several research groups. If the universe is accelerating and if the universe or some part of the universe has a charge, then there may be electromagnetic radiation…
Occultation and microlensing are different limits of the same phenomena of one body passing in front of another body. We derive a general exact analytic expression which describes both microlensing and occultation in the case of spherical…
Relativistic electrons in a structured medium generate radiative losses such as Cherenkov and transition radiation that act as a virtual light source, coupling to the photonic densities of states. The effect is most pronounced when the…
Einstein's theory of special relativity(SR) and the principle of causality imply that the speed of any moving object can not exceed that of light in a vacuum($c$).However,there were many attempts in literature discussing the particle moving…
In the context of General Relativity, radiation, either gravitational or electromagnetic, is closely associated to vorticity of observers world lines. We stress in this letter that the factor that relates the two phenomena is a circular…
When an information-carrying lightbeam is (legally) swept across a surface at more than c, simple signal-propagation arguments allow the observed behavior of the moving image (or "sprite") to include time-reversal and pair-production…
The formulas which describe the time evolution of radiation produced by a relativistic particle moving in a crystal are derived. It is shown that the conditions are realizable under which parametric (quasi-Cherenkov) radiation, transition…
One of the interesting features of Ultraluminous X-ray sources is that many of them are surrounded by luminous nebulae exhibiting diverse observational properties. In different cases the nebulae are photoionized or shock-powered. Generally,…
We derive the modified Dirac equation for an electron undergos an influence of the standard model interaction with the nuclear matter. The exact solutions for this equation and the electron energy spectrum in matter are obtained. This…
Analogy to Cherenkov radiation, when a particle moves faster than the propagation velocity of gravitational wave in matter ($v>c_{\rm{g}}$), we expect gravitational wave-Cherenkov radiation (GWCR). In the situation that a photon travels…