Related papers: Remarks on Bessel beams, signals and superluminali…
Relativistic electromagnetic plasma waves are described by a dynamical equation that can be solved not only in terms of plane waves, but for several different accelerating wavepacket solutions. Depending on the spatial and temporal…
We prepare a quasi-non-diffracting Bessel beam defined within an annular angular spectrum with a spatial light modulator. The beam propagates though a strongly scattering media and the transmitted speckle pattern is measured at one point…
We report on an experiment demonstrating the principle for transmitting quantum images through long distances. Signal and idler beams carrying correlated images have natural divergences that can be compensated by the use of collimating…
A spherical blast wave with relativistic velocity can be described by a similarity solution, that is used for theoretical models of gamma-ray bursts. We consider the linear stability of such a relativistic blast wave propagating into a…
We describe nonlinear Bessel vortex beams as localized and stationary solutions with embedded vorticity to the nonlinear Schr\"odinger equation with a dissipative term that accounts for the multi-photon absorption processes taking place at…
Wave dispersion in a pulsar plasma is discussed emphasizing the relevance of different inertial frames, notably the plasma rest frame ${\cal K}$ and the pulsar frame ${\cal K}'$ in which the plasma is streaming with speed $\beta_{\rm s}$.…
We demonstrate that beams originating from Fresnel diffraction patterns are self-accelerating in free space. In addition to accelerating and self-healing, they also exhibit parabolic deceleration property, which is in stark contrast to…
Spatial structuring of an optical pulse can lead in some cases upon free propagation to changes in its temporal profile. For example, introducing conventional angular dispersion into the field results in the pulse encountering…
We demonstrate that significant effects in the "superluminal propagation"of light-pulses cannot be observed without involving systems whose gain explodes outside the pulse spectrum. We explicitly determine the minimum norm of the gain to…
Brane observers executing appropriate motion through a partially compactified Lorentz invariant bulk spacetime, such as $M_4 \times S^1$, can send signals along the brane that are instantaneous or even travel backward in time. Nevertheless,…
It is known that superluminal transmission of information and energy contradicts Einstein's relativity. Here we announce an unusual TOE called 'nature theory' in which impossible things become possible. We present the scheme of an apparatus…
The quantum vacuum shows an intensity-dependent nonlinear index of refraction. Consequently, we may consider vacuum as a non-linear medium enabling, at sufficiently high field strengths, a direct interaction of light with light. In this…
The interaction of optical beams in bi-dispersive nonlinear media with self-focusing nonlinearity is numerically investigated. Under proper conditions, the interaction of spatially separated beams can lead to the creation of two prominent…
The influence of radiative corrections on the photon propagation in a gravitational background is investigated without the low-frequency approximation $\omega \ll m$. The conclusion is made in this way that the velocity of light can exceed…
Present low-energy bounds on Lorentz symmetry violation do not allow to exclude the possible existence of superluminal particles (superbradyons) with critical speed in vacuum $c_i \gg c$ (c = speed of light) whose kinematical properties…
This article investigates a mathematical model for bushfire propagation, focusing on the existence and properties of translating solutions. We obtain quantitative bounds on the environmental diffusion coefficient and ignition kernels,…
The title of this article is misleading. The authors have investigated a resonator but not a tunneling barrier see also Refs.\cite{Winful2} The measured superluminal group velocity and discussed is that studied on a Lorentz-Lorenz…
We investigate the time propagation of tachyonic (superluminal) and tardyonic (subluminal, ordinary) massive wave packets on cosmic scales. A normalizable wave packet cannot be monochromatic in momentum space and thus acquires a positional…
A theory of surface electromagnetic waves in gradient media exhibiting arbitrary surface gradients of dielectric permittivity and magnetic permeability has been developed. Novel low-loss propagating surface wave solutions have been found in…
The propagation and refraction of waves in dispersive media are considered. A primary objective is to determine whether waves refract as monochromatic waves by Snell's law with phase velocity or as wave packets. The refraction of wave…