Neutrino unification

Present neutrino data are consistent with neutrino masses arising from a common seed at some "neutrino unification" scale M-X. Such a simple theoretical ansatz naturally lends to quasidegenerate neutrinos that could lie in the electron-volt range with neutrino mass splittings induced by renormalization effects associated with supersymmetric thresholds. In such a scheme the leptonic analog of the Cabibbo angle theta (circle dot) describing solar neutrino oscillations is nearly maximal. Its exact value is correlated with the smallness of theta (reactor). The two leading mass-eigenstate neutrinos present in nu (e) form a pseudo-Dirac neutrino, avoiding conflict with neutrinoless double beta decay.