Lorentz violation in simple QED processes

GZK photon constraints on Planck scale Lorentz violation in QED

We show how the argument exploited by Galaverni & Sigl in Phys. Rev. Lett., 100, 021102 (2008) (see also arXiv:0708.1737) [1] to constrain Lorentz invariance violation (LV) using Ultra-High-Energy photon non observation by the AUGER experiment, can be extended to QED with Planck-suppressed LV (at order O(E/M) and O(E/M)). While the original constraints given by Galaverni & Sigl [1] happen to be...

Limits on Isotropic Lorentz Violation in QED from Collider Physics

Lorentz and CPT violation: a simple neutrino-oscillation model

We present a three-parameter model for three flavors of massless left-handed neutrinos with Fermi-point splitting and tri-maximal mixing angles. One of these parameters is the T–violating phase δ, for which the experimental results from K2K and KamLAND appear to favor a nonzero value. Future experiments, in particular MINOS, will be able to test this simple model. Possible implications for neut...

New constraints on Planck-scale Lorentz Violation in QED from the Crab Nebula

We set constraints on O(E/M) Lorentz Violation in QED in an effective field theory framework. A major consequence of such assumptions is the modification of the dispersion relations for electrons/positrons and photons, which in turn can affect the electromagnetic output of astrophysical objects. We compare the information provided by multiwavelength observations with a full and self-consistent ...

The structure of radiatively induced Lorentz and CPT violation in QED at finite temperature

We obtain the induced Lorentz-and CPT-violating term in QED at finite temperature using imaginary-time formalism and dimensional regularization. Its form resembles a Chern-Simons-like structure, but, unexpectedly, it does not depend on the temporal component of the fixed b µ constant vector that is coupled to the axial current. Nevertheless Ward identities are respected and its coefficient vani...