20 research outputs found

### Quark Masses and Mixing with A4 Family Symmetry

The successful A4 family symmetry for leptons is applied to quarks, motivated
by the quark-lepton assignments of SU(5). Realistic quark masses and mixing
angles are obtained, in good agreement with data. In particular, we find a
strong correlation between |V_{ub}| and the CP phase beta, thus allowing for a
decisive future test of this model.Comment: 9 pages, 2 figures, some discussions as to quarks and leptons are
adde

### Rotational Symmetry and A Light Mode in Two-Dimensional Staggered Fermions

To obtain a light mode in two-dimensional staggered fermions, we introduce
four new local operators keeping the rotational invariance for a staggered
Dirac operator. To split masses of tastes, three cases are considered. The mass
matrix and the propagator for free theories are analyzed. We find that one of
three cases is a good candidate for taking a single mode by the mass splitting.
In the case, it is possible that a heavy mode obtains infinite mass on even
sites or odd sites.Comment: 17 pages, one reference adde

### Quark and lepton mass matrices with $A_4$ family symmetry

Realistic quark masses and mixing angles are obtained applying the successful
$A_4$ family symmetry for leptons, motivated by the quark-lepton assignments of
SU(5). The $A_4$ symmetry is suitable to give tri-bimaximal neutrino mixing
matrix which is consistent with current experimental data. We study new
scenario for the quark sector with the $A_4$ symmetry.Comment: 16 pages, 2 figures, Talk given at International Workshop on Neutrino
Masses and Mixings, Shizuoka, Japan, 17-19 December 200

### Towards the Super Yang-Mills Theory on the Lattice

We present an entirely new approach towards a realization of the
supersymmetric Yang-Mills theory on the lattice. The action consists of the
staggered fermion and the plaquette variables distributed in the Euclidean
space with a particular pattern. The system is shown to have fermionic
symmetries relating the fermion and the link variables.Comment: 12 pages, 3 figure

### Flavor Symmetry and Vacuum Aligned Mass Textures

The mass matrix forms of quarks and leptons are discussed in theory with
permutation flavor symmetry. The structure of scalar potential is analyzed in
case that electroweak doublet Higgs fields have non-trivial flavor symmetry
charges. We find that realistic forms of mass matrices are obtained dynamically
in the vacuum of the theory, where some of Higgs bosons have vanishing
expectation values which lead to vanishing elements in quark and lepton mass
matrices. Mass textures are realized in the true vacuum and their positions are
controlled by flavor symmetry. An interesting point is that, due to the flavor
group structure, the up and down quark mass matrices are automatically made
different in the vacuum, which lead to non-vanishing generation mixing. It is
also discussed that flavor symmetry is needed to be broken in order not to have
too light scalars. The lower bounds of Higgs masses are derived from the
experimental data of flavor-changing rare processes such as the neutral K meson
mixing.Comment: 30pages, 2figures, some discussions are added, one reference is adde

### Hybrid Textures of Neutrinos

We present numerical and comprehensive analyses of the sixty hybrid textures
of neutrinos, which have an equality of matrix elements and one zero. These
textures are possibly derived from the discrete symmetry. Only six textures
among sixty ones are excluded by the present experimental data. Since there are
many textures which give similar predictions, the textures are classified based
on the numerical results. The neutrinoless double beta decay is also examined
in these textures. Our results suggest that there remain still rich structures
of the neutrino mass matrix in the phenomenological point of view.Comment: 19 pages, 9 figures; analytical discussions added, table and
reference adde

### Novel Approach to Super Yang-Mills Theory on Lattice - Exact fermionic symmetry and "Ichimatsu" pattern -

We present a lattice theory with an exact fermionic symmetry, which mixes the
link and the fermionic variables. The staggered fermionic variables may be
reconstructed into a Majorana fermion in the continuum limit. The gauge action
has a novel structure. Though it is the ordinary plaquette action, two
different couplings are assigned in the ``Ichimatsu pattern'' or the checkered
pattern. In the naive continuum limit, the fermionic symmetry survives as a
continuum (or an $O(a^0)$) symmetry. The transformation of the fermion is
proportional to the field strength multiplied by the difference of the two
gauge couplings in this limit. This work is an extension of our recently
proposed cell model toward the realization of supersymmetric Yang-Mills theory
on lattice.Comment: 26 pages, 4 figure