相关论文: Changes in extensive air showers from isotropic Lo…
We present a method for constraining Lorentz violation in the electron sector, based on observations of the photons emitted by high-energy astrophysical sources. The most important Lorentz-violating operators at the relevant energies are…
Experimental conclusions from air shower observations on cosmic-ray photons above 10^19 eV are based on the comparison to detailed shower simulations. For the calculations, the photonuclear cross-section needs to be extrapolated over…
Recent work has shown that dispersion relations with Planck scale Lorentz violation can produce observable effects at energies many orders of magnitude below the Planck energy M. This opens a window on physics that may reveal quantum…
For the high energy electromagnetic showers the thickness dependence of a) the development of electron and positron components, b) the difference between the secondary electron and positron numbers, c) the charge asymmetry of high energy…
We show that estimates of the Lorentz symmetry violation extracted from ultra-high energy cosmic rays beyond the GZK cut-off set bounds on the parameters of a Lorentz-violating extension of the Standard Model. Moreover, we argue that…
Lorentz Invariance Violation introduced as a generic modification to particle dispersion relations is used to study high energy cosmic ray attenuation processes. It is shown to reproduce the same physical effects for vacuum Cherenkov…
At very high energies the Earth magnetic field, although in many other connections conside red rather weak, acts as a strong field on photons and leptons. This paper discusses the i ntimate connection between this effect and the…
We study an extension of QED involving a light pseudoscalar (an axion-like particle), together with a very massive fermion which has Lorentz-violating interactions with the photon and the pseudoscalar, including a nonminimal…
The effect of the geomagnetic Lorentz force on the muon component of extensive air shower (EAS) has been studied in a Monte Carlo generated simulated data sample. This geomagnetic field affects the paths of muons in an EAS, causing a local…
In the last years the Lorentz Violation scheme was implemented in QFT, in special in standard model of particle physics, in an attempt to explain our actual open problems. In this work we analyze nonminimal couplings between a…
High-energy neutrino astronomy will be capable of observing particles at both extremely high energies and over extremely long baselines. These features make such experiments highly sensitive to the effects of CPT and Lorentz violation. In…
A cornerstone of special relativity is Lorentz Invariance, the postulate that all observers measure exactly the same photon speeds independently on the photon energies. However, a hypothesized structure of spacetime may alter this…
This paper explores the annihilation process of an electron-positron pair into a heavier lepton-antilepton pair, taking into account the presence of an external classical magnetic field. Additionally, it investigates corrections arising…
Various decay processes, such as the decay of a spin-1 particle into two photons or the gravitational decay of a spin-1/2 fermion, are forbidden in the vacuum by a combination of requirements, including angular momentum conservation,…
Two-photon decays of vector mesons and dilepton decays of scalar mesons which are forbidden in vacuum and can occur in dense baryonic matter due to the explicit violation of Lorentz symmetry are described within a quark model of the…
We discuss that hadron-induced atmospheric air showers from ultra-high energy cosmic rays are sensitive to QCD interactions at very small momentum fractions x where nonlinear effects should become important. The leading partons from the…
Anisotropy in the speed of light that has been constrained by Michelson-Morley-type experiments also generates anisotropy in the Coulomb interactions. This anisotropy can manifest itself as an energy anisotropy in nuclear and atomic…
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…
We present a brief review of our recent work [1] on asymmetrically warped brane models, where the background metric is characterized by different time and space warp factors. In particular we examine the case of bulk photons and we show…
We consider an environmentally dependent violation of Lorentz invariance in scalar-tensor models of modified gravity where General Relativity is retrieved locally thanks to a screening mechanism. We find that fermions have a modified…