Neutrino propagation in noncommutative spacetimes

A bstract One-loop θ-exact quantum corrections to the neutrino propagator are computed in noncommutative U ⋆ (1) gauge-theory based on Seiberg-Witten maps. Our closed form results show that the one-loop correction contains a hard 1/ǫ UV divergence, as well as a logarithmic IR-divergent term of the type ln , thus considerably softening the usual UV/IR mixing phenomenon. We show that both of these problematic terms vanish for a certain choice of the noncommutative parameter θ which preserves unitarity. We find non-perturbative modifications of the neutrino dispersion relations which are assymp-totically independent of the scale of noncommutativity in both the low and high energy limits and may allow superluminal propagation. Finally, we demonstrate how the prodigious freedom in Seiberg-Witten maps may be used to affect neutrino propagation in a profound way.