Hironobu Kataoka

SU(3)×SU(2)×U(1) Chiral Models from Intersecting D4-/D5-Branes

a ) on each of the d two-tori, where I = 1 for D4-branes and I =1 , 2 for D5-branes. When the a-th stack and the b-th stack intersect, we refer to their intersections as an a-b sector. The intersection number of the a-b sector is given by

The supersymmetric Dirac operator on noncommutative geometry

We extend naturally the spectral triple which define noncommutative geometry (NCG) in order to incorporate supersymmetry and obtain supersymmetric Dirac operator D_M which acts on Minkowskian manifold. Inversely, we can consider the projection which reducts D_M to

The minimum supersymmetric standard model on noncommutative geometry

\not{D}

Unique flipped SO(10) SUSY-GUT from Z orbifold

, the Dirac operator of the original spectral triple. We investigate properties of the Dirac operator, some of which are inherited from the original Dirac operator. Z/2 grading and real structure are also supersymmetrically extended. Using supersymmetric invariant product, the kinematic terms of chiral and antichiral supermultiplets which represent the wave functions of matter particles and their superpartners are provided by D_M. Considering the fluctuation given by elements of the algebra to the extended Dirac operator, we can expect to obtain vector supermultiplet which includes gauge field and to obtain super Yang-Mills theory according to the supersymmetric version of spectral action principle.

All possible electroweak models from Z orbifold

The minimum supersymmetric standard model on noncommutative geometry Masafumi Shimojo1,∗, Satoshi Ishihara2, Hironobu Kataoka2, Atsuko Matsukawa2, and Hikaru Sato2 1Department of Electronics and Information Engineering, Fukui National College of Technology, Geshicho, Sabae, Fukui 916-8507, Japan 2Department of Physics, Hyogo University of Education, Shimokume, Kato, Hyogo 673-1494, Japan ∗E-mail: shimo0@ei.fukui-nct.ac.jp

Construction of minimal supersymmetric Z orbifold GUT models

Abstract We analyze all possible SU(5) and SO(10) SUSY-GUT models obtained from heterotic superstrings compactified on the Z orbifold with two Wilson lines. It is shown that there is no anomaly-free flipped SU(5) model. On the other hand we obtain only one anomaly-free lipped SO(10) model with three generations which breaks directly to electroweak symmetries.

Dilaton incoming vertices of the closed superstring and the heterotic string

Abstract Considering all possible combinations of two Wilson lines, it is shown that only three independent electroweak models with three generations are obtained from Z orbifold compactification. We obtain this result by analyzing particle spectra of both untwisted and twisted sectors explicitly.

Supergravity on the noncommutative geometry

Abstract Taking into account modular invariance and absence of target space duality anomalies as well as chiral gauge anomalies, we found that the Z3 orbifold compactification with two Wilson lines gives a unique flipped SO(10) minimal supersymmetric grand unified model, where the hidden sector gauge group is also uniquely determined by the duality-anomaly-free condition as SU(5). We propose a dynamical mechanism of GUT symmetry breaking which may generate two hierarchical mass scales as M GUT ≈ ( g st 2 4π ) M st .

D = 4, N=1, type IIA orientifolds

Abstract BRST- and conformally-invariant incoming vertices for the dilaton are constructed in the closed superstring and the heterotic string theories. The BRST-invariant (0, 0) conformal field corresponding to the dilaton is determined up to a BRST cohomology transformation.

The superspace representation of super Yang–Mills theory on noncommutative geometry

Two years ago, we found the supersymmetric counterpart of the spectral triple which specified noncommutative geometry. Based on the triple, we derived gauge vector supermultiplets, Higgs supermultiplets of the minimum supersymmetric standard model and its action. However, unlike the famous theories of Connes and his co-workers, the action does not couple to gravity. In this paper, we obtain the supersymmetric Dirac operator