Bottom-up model for maximal [Formula Presented] mixing

Abstract

We construct a model which provides maximal mixing between a pseudo-Dirac (Formula presented) pair, based on a local (Formula presented) symmetry. Its strengths, weaknesses and phenomenological consequences are examined. The mass gap necessitated by the pseudo-Dirac structure is most naturally associated with the LSND anomaly. The solar neutrino problem then requires a light mirror or sterile neutrino. By paying a fine-tuning price to nullify the mass gap, one can also invoke (Formula presented) for the solar problem. The model predicts a new intermediate range force mediated by the light gauge boson of (Formula presented) Through the mixing of μ, τ and e, this force couples to electrons and..