Related papers: Comment on "Gain-assisted Superluminal Light Propa…
This study investigates the propagation of an ultrafast laser pulse through a liquid medium. A femtosecond laser oscillator with a pulse duration of less than 8 fs is used. By conducting experiments with coumarin and fluorescein dyes in…
The group-velocity of evanescent waves (in undersized waveguides, for instance) was theoretically predicted, and has been experimentally verified, to be Superluminal (v_g > c). By contrast, it is known that the precursor speed in vacuum…
During the last few years deep underwater neutrino telescopes of a new generation with dimensions close to 100 m or more were taken into operation. For the correct track reconstruction and for the interpretation of light pulses from…
Superluminal phenomena have been reported in many experiments of electromagnetic wave propagation, where the superluminal behaviors of evanescent waves are the most interesting ones with the important physical significances. Consider that…
As generally known, the speed of propagation of light in solid state bodies can be different from the speed of light in vacuum. That the mere presence of electric or magnetic fields in the vacuum can suffice to influence the speed of light,…
On-going projects to discover Type Ia supernovae at redshifts z = 0.3 - 1, coupled with improved techniques to narrow the dispersion in SN Ia peak magnitudes, have renewed the prospects for determining the cosmic deceleration parameter q_0.…
We report measurements of intensity distributions of transmitted microwave radiation in quasi-1D samples with lengths L as large as the localization length $\xi$. In contrast to negative exponential statistics found in the diffusive limit,…
There is still no general consensus on how one can describe the out-of-equilibrium phenomena in matter induced by an ultrashort light pulse. We investigate the pulse-induced dynamics in a layered Dirac semimetal SrMnBi2 by pump-and-probe…
We show that a laser beam can be diffracted by a more concentrated light pulse due to quantum vacuum effects. We compute analytically the intensity pattern in a realistic experimental configuration, and discuss how it can be used to measure…
Various experiments have shown superluminal group and signal velocities recently. Experiments were essentials carried out with microwave tunnelling, with frustrated total internal reflection, and with gain-assisted anomalous dispersion.…
In this paper the fields generated by an electric dipole and a gravitational quadrapole are shown to propagate superluminally in the nearfield of the source and reduce to the speed of light as the fields propagate into the farfield. A…
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…
In the context of quantum gravity phenomenology, we study the Unruh effect in the presence of superluminal dispersion relations. In particular, we estimate the response function and the probability rate for an accelerated detector coupled…
Group velocity control is demonstrated for x-ray photons of 14.4 keV energy via a direct measurement of the temporal delay imposed on spectrally narrow x-ray pulses. Sub-luminal light propagation is achieved by inducing a steep positive…
Reaching light intensities above $10^{25}$ W/cm$^{2}$ and up to the Schwinger limit ($10^{29}$ W/cm$^{2}$) would enable testing decades-old fundamental predictions of Quantum Electrodynamics. A promising yet challenging approach to achieve…
The peculiar characteristics of random laser emission have been studied in many different media, leading to a classification of the working regimes based on the statistics of spectral fluctuations. Alongside such studies, the possibility to…
A new determination of the upper limit to the cosmic diffuse background radiation, at ~110 nm, of 300 photons s-1 cm-2 sr-1 nm-1, is placed in the context of diffuse background measurements across the entire electromagnetic spectrum,…
In this Chapter, we give a brief review of the state of the art of theoretical and experimental studies of quantum fluids of light. Such systems consist of ensembles of photons that acquire a finite mass from spatial confinement or…
In extreme scattering events, the brightness of a compact radio source drops significantly, as light is refracted out of the line of sight by foreground plasma lenses. Despite recent efforts, the nature of these lenses has remained a…
The relative pair dispersion of galaxies has for the past decade been the standard measure of the thermal energy of fluctuations in the observed galaxy distribution. This statistic is known to be unstable, since it is a pair-weighted…