Related papers: Superluminal propagation from IR physics
The peridynamic analogue of the wave equation does not have finite speed propogation. We show, for one dimensional linear peridynamics, that solutions do nonetheless satisfy estimates analogous to those satisfied by solutions of the wave…
In this Chapter the time-domain analysis of the velocity of the electromagnetic field pulses generated by a spatially compact source in free space is presented. Recent simulations and measurements of anomalous superluminal, subluminal, and…
Recently it was suggested that the observation of superluminal neutrinos by the OPERA collaboration may be due to group velocity effects resulting from close-to-maximal oscillation between neutrino mass eigenstates, in analogy to known…
We analyze the propagation of a pulse across a vacuum gap separating opposite flat parallel faces of two transparent dielectrics by means of an explicitly causal and retarded propagator constructed directly from the free-space wave…
Coule's primary objection to the Alcubierre "warpdrive" is that the material producing the warp field needs to be superluminal. This difficulty is solved by placing the drive material inside its own warp field (making the drive system part…
Gravitational waves offer a key insight into the viability of classes of gravitational theories beyond general relativity. The observational constraints on their speed of propagation can provide strong constraints on generalized classes of…
The concepts of phase, group, and front velocities introduced by Sommerfeld will be reviewed, and applied to superluminal phenomena, with a brief review of optical experiments that evince superluminal group velocities. We shall discuss the…
General relativity provides an appropriate framework for addressing the issue of sub- or superluminality as an apparent effect. Even though a massless particle travels on the light cone, its average velocity over a finite path measured by…
Steep or near-vertical Floquet dispersion in photonic time crystals (PTCs) is often read as fast, even apparently superluminal, transport. Here, we demonstrate that this anomaly arises from modulation-driven geometric drift, not energy…
We present a model for a vacuum-like effective medium composed of the absorbing and gain media under the special designed parameters. Within the linear response theory, we prove that any pulse signal (with or without a discontinuity)…
As a prototypical massive field theory we study the scalar field on the recently introduced Finsler spacetimes. We show that particle excitations exist that propagate faster than the speed of light recognized as the boundary velocity of…
Some recent experiments, performed at Berkeley, Cologne, Florence and Vienna led to the claim that something seems to travel with a speed larger than the speed c of light in vacuum. Various other experimental results seem to point in the…
From an extended relativistic dynamics for a particle moving in a cosmic background field with temperature T, we aim to obtain the speed of light with an explicit dependence on the background temperature of the universe. Although finding…
Within the low-energy effective field theories of QED and gravity, the low-energy speed of light or that of gravitational waves can typically be mildly superluminal in curved spacetimes. Related to this, small scattering time advances…
The propagation of light-pulse with negative group-velocity in a nonlinear medium is studied theoretically. We show that the necessary conditions for these effects to be observable are realized in a three-level $\Lambda$-system interacting…
We study the interface propagation in superconductors by means of a variational method. We compute the lower and upper bounds for which the planar front speed propagation is valid. To take into account delay or memory effects in the front…
We address a dynamical, spherically symmetric background in beyond Horndeski theory and formulate a set of linear stability conditions for high energy perturbation modes above an arbitrary solution. In this general setting we derive speeds…
We introduce a method to test if a given velocity definition corresponds to an actual physical flow, when the pulse propagation in dispersive medium is considered. i) We calculate the mean arrival time between two positions in space, using…
We consider rectilinear free-space propagation of electromagnetic wavepackets using electromagnetic field theory, scalar wavepacket propagation, and quantum-mechanical formalism. We demonstrate that spatially localized wavepackets are…
Maxwell's equations applied to a superconducting wire (aluminum) covered with a thick nonsuperconducting sheath (copper), in combination with the superfluid velocity equation for Cooper pairs which obeys DeWitt's minimal coupling rule,…