RADIATIVE-CORRECTIONS AND UNCERTAINTIES IN SEESAW FORMULAS FOR NEUTRINO MASSES

Evaluation of radiative corrections and uncertainties in the coefficie nts C-nu i(q) (C-nu i((l))) when the Dirac mass of the upquark (charge d lepton) occurs in the quadratic seesaw formula, reveals that C-nu ta u((q)) which is nearly 65% more than the earlier value, is stable agai nst uncertainties in the input parameters, but C-nu e((q)) and C-nu mu ((q)) have larger uncertainties dominating over their central values. The leptonic coefficients C-nu i((l)) (i = e, mu, tau) estimated here for the first time show that C-nu tau((l)) is renormalized by 20-40% w hile C-nu mu((l)) and C-nu e((l)) are reduced by 60-80% from their can onical value. All the leptonic coefficients are found to possess small er uncertainties. These results are generally valid in two-step breaki ngs of SO(10) and other grand unified theories.