Masafumi Shimojo

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}

Vacuum structure of a generalized degenerate 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.

Supergravity on the noncommutative geometry

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

A Flipped SO(10) Model from Z6-I Orbifold

Abstract By considering the possible scalar background fields on the orbifold, we show that the vacuum structure of the Z orbifold is characterized by p[p+r( G )] 2+16 parameters, where p is the number of compactified dimensions and r(G) is the number of generators of the group for the background gauge field. We also give a prescription for contructing generalized degenerate orbifold models by a purely stringly method without using the potential argument.

String flipped SO(10) model from Z 4 orbifold

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

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

\mathcal{D}_M^{(SG)}

The superspace representation of Super Yang-Mills theory on NCG

on the Riemann-Cartan curved space replacing derivatives which appear in that of the triple with the covariant derivatives of general coordinate transformation. We apply the supersymmetric version of the spectral action principle and investigate the heat kernel expansion on the square of the Dirac operator. As a result, we obtain a new supergravity action which does not include the Ricci curvature tensor.