相关论文: Changes in extensive air showers from isotropic Lo…
If the observation by OPERA of apparently superluminal neutrinos is correct, the Lagrangian for second-generation leptons must break Lorentz invariance. We calculate the effects of an energy-independent change in the neutrino speed on…
Lorentz symmetry breaking at very high energies may lead to photon dispersion relations of the form omega^2=k^2+xi_n k^2(k/M_Pl)^n with new terms suppressed by a power n of the Planck mass M_Pl. We show that first and second order terms of…
Present and future ultra-high-energy-cosmic-ray facilities (e.g., the Pierre Auger Observatory with South and North components) and TeV-gamma-ray telescope arrays (e.g., HESS or VERITAS and CTA) have the potential to set stringent indirect…
If Lorentz violation exists, it will affect the thresholds for pair creation processes. Lorentz-violating operators that change the maximum velocities of charged particles may increase or decrease the extinction rate of gamma-rays moving…
We have performed a calculation in the parton-model approximation of a nonstandard decay process in isotropic modified Maxwell theory coupled to standard Dirac theory, with a single Lorentz-violating parameter $\kappa$ in the photonic…
Inspired by recent astrophysical observations of leptonic excesses measured by satellite experiments, we consider the impact of some general models of the dark sector on the muon production in extensive air showers. We present a compact…
Ultra-high-energy physics is about to enter a new era thanks to the impressive results of experiments such as the "Large High Altitude Air Shower Observatory" (LHAASO), detecting photons of up to $1.4\times 10^{15}$ eV (PeV scale). These…
In energetic nonthermal sources such as gamma-ray bursts, AGN or galactic jet sources, etc., one expects both relativistic and transrelativistic shocks acompanied by violent motions of moderately relativistic plasma. We present general…
The development of cosmic ray air showers can be influenced by atmospheric electric fields. Under fair weather conditions these fields are small, but the strong fields inside thunderstorms can have a significant effect on the…
Quantum gravity theories often modify spacetime symmetries. In particular, Lorentz invariance may be violated when approaching the Planck scale. Although the scales at which interactions occur in extensive air showers induced by…
We entertain the idea that a suitable background of cold (very low momentum) pseudoscalar particles or condensate, may trigger a background that effectively generates Lorentz-invariance violation. This aether-like background induces a…
One of the possible consequences of the existence of extra degrees of freedom beyond the electroweak scale is the increase of neutrino-nucleon cross sections ($\sigma_{\nu N}$) beyond Standard Model predictions. At ultra-high energies this…
The possibility of the breaking of Lorentz symmetry has been discussed in many models of quantum gravity. In this paper we follow the Lorentz violation model in Ref. [1] (i.e., our previous work) to discuss the Doppler frequency shift of…
In the electromagnetism of loop quantum gravity, two helicities of a photon have different phase velocities and group velocities, termed as "vacuum birefringence". Two novel phenomenons, "peak doubling" and "de-polarization", are expected…
We investigate the implications of energy-dependence of the speed of photons, one of the candidate effects of quantum-gravity theories that has been most studied recently, from the perspective of observations in different reference frames.…
We propose an innovative test of Lorentz symmetry by observing pairs of simultaneous parallel extensive air showers produced by the fragments of ultrahigh-energy cosmic ray nuclei which disintegrated in collisions with solar photons. We…
The aim of this brief review is to present a case study of how astrophysics data can be used to get bounds on Lorentz-violating parameters. For this purpose, a particularly simple Lorentz-violating modification of the Maxwell theory of…
In the presence of Lorentz violation, the Cerenkov-like process $\gamma\rightarrow\gamma+\pi^{0}$ may become allowed for sufficiently energetic photons. Photons above the threshold would lose energy rapidly through pion emission. The fact…
Searches for Lorentz violation were recently extended to the weak sector, in particular neutron and nuclear $\beta$ decay [1]. From experiments on forbidden $\beta$-decay transitions strong limits in the range of $10^{-6}$-$10^{-8}$ were…
Ultrahigh energy cosmic rays that produce giant extensive showers of charged particles and photons when they interact in the Earth's atmosphere provide a unique tool to search for new physics. Of particular interest is the possibility of…