Symmetry Breaking in SO(10) Grand Unified Theory and Quark Masses.

摘要

A model of SO(10) grand unified theory is proposed, where the quark mass spectrum problem occurring in SO(10) breaking schemes with intermediate SU(4)xSU(2)/sub L/xSU(2)/sub R/ or SU(3)/sub C/xU(1)/sub B-L/xSU(2)/sub L/xSU(2)/sub R/ symmetry is solved owing to additional discrete symmetry. With account of this discrete symmetry breaking and from the condition of existence of only one light Higgs boson, a relation between b and t quark masses is obtained, which enables one to fix up the ratio of grand unification scale M/sub x/ to quark-lepton symmetry breaking scale M/sub c/. The concrete values of M/sub x/, M/sub c/ as well as SU(2)/sub R/-symmetry breaking scale M/sub R/ depend on experimental value of Weinberg angle and agree with the proton decay experiments. The problems of mixing of three generations of quarks are being studied within the proposed model. The obtained Kobayashi-Maskawa mixing angles are in good agreement with experiment. 13 refs.; 2 figs. (Atomindex citation 19:069599)