Related papers: Photon emission and decay from generic Lorentz Inv…
We construct models for first- and second-order Fermi acceleration of particles, incorporating generic frame transformations, dispersion relations, and conservation laws. Within this framework, we study deformations of Lorentz symmetry via…
If textbook Lorentz invariance is actually a property of the equations describing a sector of the excitations of vacuum above some critical distance scale, several sectors of matter with different critical speeds in vacuum can coexist and…
It is by now clear that infrared sector of QED has an intriguingly complex structure. Based on earlier pioneering works on this subject, two of us recently proposed a simple modification of QED by constructing a generalization of the $U(1)$…
The modified Lorentz transformation of a distance-dependent special theory of relativity - which will be briefly summarized - predicts the possibility of superluminal velocity of very distantly moving material bodies to be connected with…
If textbook Lorentz invariance is actually a property of the equations describing a sector of the excitations of vacuum above some critical distance scale, several sectors of matter with different critical speeds in vacuum can coexist and…
We perform the covariant canonical quantization of the CPT- and Lorentz-symmetry-violating photon sector of the minimal Standard-Model Extension, which contains a general (timelike, lightlike, or spacelike) fixed background tensor…
The general charge-conserving effective scalar field theory incorporating violations of Lorentz symmetry is presented. The dispersion relation is used to infer the effects of spin-independent Lorentz violation on point-particle motion. A…
CPT-Violating photons are well-known to have problems with energy positivity in certain cases and therefore have not been convincingly quantized to date. We find that by adding a small mass term, consistent with experimental bounds, the…
Many quantum theories of gravity propose Lorentz violating dispersion relations of the form $\omega = |k|\, f(|k|/M)$, with recovery of approximate Lorentz invariance at energy scales much below $M$. We show that a quantum field with this…
We show that violation of the Lorentz symmetry in quantum electrodynamics can suppress the rates of the interactions crucial for the formation of photon-induced air showers, such as pair production on nuclei and in the geomagnetic field. As…
A charged particle moving through a medium emits Cherenkov radiation when its velocity exceeds the phase velocity of light in that medium. Under the influence of a strong electromagnetic field, quantum fluctuations can become polarized,…
We explore the possibility that the weak interaction violates Lorentz, and in particular rotational, invariance in neutron and allowed nuclear beta decay. A broad class of Lorentz-violating effects is considered, in which the standard…
The scattering of photons off photons at the one-loop level is investigated. We give a short review of the weak field limit, as given by the first order term in the series expansion of the Heisenberg-Euler Lagrangian. The dispersion…
We study CPT and Lorentz violation in the electroweak gauge sector of the Standard Model in the context of the Standard-Model Extension. In particular, we consider the Lorentz-violating and CPT-odd Chern-Simons like parameter for the W…
In this paper three things are done. (i) We investigate the analogues of Cerenkov radiation for the decay of a superluminal neutrino and calculate the Cerenkov angles for the emission of a photon through a W loop, and for a collinear…
A system of equations governing the structure of a steady, relativistic radiation dominated shock is derived, starting from the general form of the transfer equation obeyed by the photon distribution function. Closure is obtained by…
On January 14, 2019, the Major Atmospheric Gamma Imaging Cherenkov telescopes detected GRB 190114C above 0.2 TeV, recording the most energetic photons ever observed from a gamma-ray burst. We use this unique observation to probe an energy…
The power and the probability of electromagnetic radiation from an electron in a constant background tensor field violating Lorentz invariance are calculated. The case of a background field of the quasielectric type is considered. The…
The Imaging Atmospheric Cherenkov technique allows to detect very high energy gamma rays from few tens of GeV to hundreds of TeV using ground-based instrumentation. At these energies a gamma ray generates a shower of secondary particles…
The decay of an unstable system is usually described by an exponential law. Quantum mechanics predicts strong deviations of the survival probability from the exponential: indeed, the decay is initially quadratic, while at very large times…