To be published in Phys. Rev. D61 (2000),0350xx
SO(10) \times SO(10) Universal Seesaw Model
and its Intermediate Mass Scales
On the basis of the universal seesaw mass matrix model,
which is a promising model of the unified description of the
quark and lepton mass matrices, the behaviors of the gauge
coupling constants and intermediate energy scales in the
SO(10)_L \times SO(10)_R model are investigated related to
the neutrino mass generation scenarios. The non-SUSY model
cannot give favorable values of the intermediate energy
scales to explain the smallness of the neutrino masses,
while the SUSY model can give the plausible values if the
number n_\phi of the weak doublet Higgs scalars is n_\phi
\geq 3.
To be published in Phys. Rev. D60, (1999) 077301.
Universal Seesaw Mass Matrix Model
with an S_3 Symmetry
Stimulated by the phenomenological success of the universal
seesaw mass matrix model, where the mass terms for quarks and
leptons f_i (i=1,2,3) and hypothetical super-heavy fermions
F_i are given by \overline{f}_L m_L F_R +\overline{F}_L m_R f_R
+ \overline{F}_L M_F F_R + h.c. and the form of M_F is
democratic on the bases on which m_L and m_R are diagonal,
the following model is discussed: The mass terms M_F are
invariant under the permutation symmetry S_3, and the mass
terms m_L and m_R are generated by breaking the S_3 symmetry
spontaneously. The model leads to an interesting relation
for the charged lepton masses.