Confronting CERN LEP data, the proton lifetime, and small neutrino masses by threshold effects in SO(10) with SU(2)LxU(1)RxSU(4)C intermediate breaking

We derive analytic formulas for mass scales and the GUT coupling constant in SO(10) with SU(2)LxU(1)RxSU(4)C (≡G214) intermediate breaking including two-loops and threshold effects. We find that the mass-scale predictions are in agreement with the CERN LEP data and proton-lifetime limit provided threshold effects due to heavy Higgs scalars are included. In one case the predicted proton lifetime is close to the experimental limit, while the νe mass is small, the νμ mass is accessible to laboratory experiments, and the ντ mass is consistent with the 17 keV neutrino. In the most interesting case the predicted proton lifetime is accessible to the Superkamiokande experiments and the νe and νμ masses have the right values needed for understanding the solar neutrino problem using the Mikheyev-Smirnov-Wolfenstein mechanism. The ντ mass is found to be consistent with the requirement for the dark matter of the Universe