Takeo Matsuoka

Realistic Models from the E8 ×E8′ Superstring Theory

On etudie les modeles qui sont realistes par rapport aux contraintes posees par la longevite du proton, la creation de masse du quark, les masses nulle ou petite des neutrinos

Large Lepton Flavor Mixing and E6-Type Unification Models

There are experimental indications of large flavor mixing between

Supersymmetry breaking without a messenger gauge group

\nu_{\mu }

Fermion Masses and Mixings in a String Inspired Model

and

Gauge hierarchies in the E8 × E′8 superstring theory

\nu_{\tau}

A large Majorana mass from Calabi-Yau superstring models

. In the unification models, in which the massless sector includes extra particles beyond the standard model, there possibly appear the mixings between quarks (leptons) and the extra particles. When large mixings occur, lepton flavor mixings can be quite different from quark flavor mixings. By taking the string inspired

How Can We Obtain a Large Majorana-Mass in Calabi-Yau Models?

SU(6) \times SU(2)_R

Effective Messenger Sector from Dynamical Supersymmetry Breaking

model with global flavor symmetries, we obtain the neutrino flavor mixing

Extra U(1) Phenomenology from the E8 ×E8 Superstring Theory

\sin \theta_{23} \simeq \lambda = \sin \theta_C

The Aligned SU(5) ×U(1)2 Model

around the unification scale. It can be expected that due to large Yukawa couplings of neutrinos, the renormalization effect increases