Pseudo-Dirac solar neutrinos?

The compatibility of a recent possible explanation of the solar-neutrino puzzle and the result of Boris et al. on limits on neutrino mass is discussed. It is shown that if the electron and muon Majorana neutrinos combine to form a pseudo-Dirac particle of mass ~35 eV, then the radiative corrections will generate a mass-square difference 3×10−5 eV, which explains why Davis and his collaborators find fewer solar neutrinos than predicted. This idea can be naturally embedded in superstring theories