High-energy tests of Lorentz invariance - art. no. 116008

We develop a perturbative framework with which to discuss departures from e xact Lorentz invariance and explore their potentially observable ramificati ons. Tiny noninvariant terms introduced into the standard model Lagrangian are assumed to he renormalizable (dimension less than or equal to 4), invar iant under SU(3) x SU(2) x U(1) gauge transformations, and rotationally and translationally invariant in a preferred frame. There are a total of 46 in dependent CPT-even perturbations of this kind, all of which preserve anomal y cancellation. They define the energy-momentum eigenstates and their maxim al attainable velocities in the high-energy limit. The effects of these per turbations increase rapidly with energy in the preferred frame, more rapidl y than those of CPT-odd perturbations. Our analysis of Lorentz-violating ki nematics reveals several striking new phenomena that are relevant both to c osmic-ray physics (e.g., by undoing the Greisen, Zatsepin, and Kuz'min cuto ff) and neutrino physics (e.g., by generating novel types of neutrino oscil lations). These may lead to new and sensitive high-energy tests of special relativity. [S0556-2821(99)00111-3].