Higgs bosons in SO(10) and partial unification

The implications of the existence of a partial unification, previous to the grand unification into SO(10) are studied. Special emphasis is given to the influence of the Higgs bosons in the theory. We calculate their contribution to the β-functions of the partialunification roups of most phenomenological interest and it is found that the results previously calculated for the partial and grand unification masses are in general drastically changed. After making an extended “survival hypothesis” about the masses of the Higgses, we find that the partial unification mass (PUM) should be typically 10^10?11 GeV. The masses of the neutrinos are related to the PUM and we obtain m_ντ ～ 1–10 eV. Neutron oscillations can appear, but at a negligible rate. Proton decay may occur at the expected rate, although in some models it is highly suppressed. The result for the ratio m_b/m_τ is smaller than in SU(5) and the simplest SO(10) version.