Related papers: Variations of the Hidden Sector in a Realistic Int…
In this paper we consider the Spontaneous Symmetry Breaking Mechanism (SSBM) in the Standard Model of particles in the unitary gauge. We show that the computation usually presented of this mechanism can be conveniently performed in a…
I describe the main features of new intersecting D4- and D5-brane orbifold models that yield the non-supersymmetric standard model, up to vector-like matter and, in some cases, extra U(1) factors in the gauge group. There are six-stack…
All five-dimensional non-abelian gauge theories have a $U(1)_I$ global symmetry associated with instantonic particles. We describe an obstruction to coupling $U(1)_I$ to a classical background gauge field that occurs whenever the theory has…
We propose a new mechanism of spontaneous supersymmetry breaking. The existence of extra dimensions with nontrivial topology plays an important role. We investigate new features resulted from the mechanism in two simple supersymmetric Z_2…
We study the supersymmetric GUT models where the supersymmetry and GUT gauge symmetry can be broken by the discrete symmetry. First, with the ansatz that there exist discrete symmetries in the branes' neighborhoods, we discuss the general…
By employing D6-branes intersecting at angles in $D = 4$ type I strings, we construct {\em five stack} string GUT models (PS-II class), that contain at low energy {\em exactly the Standard model} with no extra matter and/or extra gauge…
We explore supersymmetric Type I string-motivated three-family scenarios in which the Standard Model is embedded within two sets of intersecting D branes with U(1)-extended Pati-Salam gauge groups. We study a model inspired by the Shiu-Tye…
We investigate simple extensions of the Mirror Twin Higgs model in which the twin color gauge symmetry and the discrete $Z_2$ mirror symmetry are spontaneously broken. This is accomplished in a minimal way by introducing a single new…
We construct the first three family N=1 supersymmetric string model with Standard Model gauge group SU(3)_C x SU(2)_L x U(1)_Y from an orientifold of type IIA theory on T^6/(Z_2 x Z_2) and D6-branes intersecting at angles. In addition to…
We review several geometric aspects and properties of the orbifold T6/Z(2)xZ(6')xOR with discrete torsion, that are crucial with respect to global model building and the search for discrete gauge symmetries in the context of intersecting…
Intersecting D-brane worlds provide phenomenologically appealing constructions of four dimensional low energy string vacua. In this talk, a Z_4 x Z_2 orbifold background is taken into account. It is possible to obtain supersymmetric and…
We examine the possibility that dark matter may be the manifestation of dark forces of a hidden sector, i.e. "Dark Force = Dark Matter." As an illustrative and minimal example we consider the hidden SU(2)_h x U(1)_h gauge group. The hidden…
We discuss the appearance of non-supersymmetric D6-brane GUT model constructions. We focus on the construction of the first examples of flipped SU(5) and SU(5) GUTS which have only the SM at low energy. These constructions are based on 4D…
We consider the possibility of unification of the Supersymmetric Standard Model gauge groups with those of the dynamical supersymmetry breaking (DSB) sector in theories with gauge mediated supersymmetry breaking. We find constraints on the…
We propose low energy 6-dimensional N=2 supersymmetric SU(6) models on $M^4\times T^2/(Z_2)^3$ and $M^4\times T^2/(Z_2)^4$, where the orbifold $SU(3)_C\times SU(3)$ model can be embedded on the boundary 4-brane. For the zero modes, the…
Little experimental data bears on the question of whether there is a spontaneously broken hidden sector that has no Standard Model quantum numbers. Here we discuss the prospects of finding evidence for such a hidden sector through…
After reviewing the general structure of supersymmetric intersecting brane world models, we discuss the issue of stringy gauge coupling unification for a natural class of MSSM-like models.
We found an additional symmetry hidden in the fermion and Higgs sectors of the Standard Model. It is connected to the centers of the SU(3) and SU(2) subgroups of the gauge group. A lattice regularization of the whole Standard Model is…
Orientifold vacua allow the simultaneous presence of supersymmetric bulks, with one or more gravitinos, and non-supersymmetric combinations of BPS branes. This ``brane supersymmetry breaking'' raises the issue of consistency for the…
We show that small soft terms can create a supersymmetry breaking minimum along a pseudo-flat direction of a hidden sector which would otherwise be incapable of spontaneous supersymmetry breaking. As this minimum lies along a pseudo-flat…