Related papers: Supersymmetric Composite Models on Intersecting D-…
We construct a supersymmetric standard model in the context of the $Z_{12-I}$ orbifold compactification of the heterotic string theory. The gauge group is $SU(3)_c\times SU(2)_L\times U(1)_Y\times U(1)^4\times[SO(10)\times U(1)^3]'$. We…
As a further elaboration of the proposal of Ref. [1] we address the construction of Standard-like models from configurations of stacks of orientifold planes and D-branes on an internal space with the structure ${(Gepner model)^{c=6} \times…
We search for the three-generation standard-like and/or Pati-Salam models from the $SO(32)$ heterotic string theory on smooth, quotient complete intersection Calabi-Yau threefolds with multiple line bundles, each with structure group…
A supersymmetric model with four generations is proposed, in which the top quark is approximately degenerate in mass with the $W^{\pm}$ gauge boson, $m_t\simeq m_W$, leading to values of $R_b$ in better agreement with the present…
We discuss a possibility whether a model of grand gauge-Higgs unification incorporating family unification in higher dimensions can be constructed. We first extend a five dimensional $SU(6)$ grand gauge-Higgs unification model to a five…
We investigate intersecting D6-branes on an orientifold of type IIA theory in the orbifold background T^6/(Z_4 x Z_2) with the emphasis on finding chiral spectra. RR tadpole cancellation conditions and the scalar potential at disc level are…
We construct a one-parameter set of intersecting D4-brane models, with six stacks, that yield the (non-supersymmetric) standard model plus extra vector-like matter. Twisted tadpoles and gauge anomalies are cancelled, and the model contains…
We construct new semi-realistic Type IIB flux vacua on $Z_2\times Z_2$ orientifolds with three- and four- Standard Model (SM) families and up to three units of quantized flux. The open-string sector is comprised of magnetized D-branes and…
This work considers the remarkable suggestion that the three families of quarks and leptons may be unified, together with the Higgs and gauge fields of the Standard Model (SM), into a single "particle", namely the $\textbf{248}$ vector…
We construct new Standard-like models on Type II orientifolds. In Type IIA theory on $\mathbf{T^6/(\Z_2\times \Z_2)}$ orientifold with intersecting D6-branes, we first construct a three-family trinification model where the $U(3)_C\times…
For supersymmetric extensions of the Standard Model we construct some expressions that include Yukawa couplings for the third and second generations and receive relatively small quantum corrections. This implies that they slightly depend on…
We use a $U(2)\times U(1)$ horizontal symmetry in order to construct supersymmetric models where the flavor structure of both quarks and leptons is induced naturally. The supersymmetric flavor changing neutral currents problem is solved by…
We study the predictions of the simplest SU(5) grand unified model within the framework of minimal supergravity, including constraints from the radiative breaking of electroweak symmetry. As a consequence of the unification of the $b$-quark…
We present an $E_6$ Grand Unified model with a realistic pattern of fermion masses. All standard model fermions are unified in three fundamental 27-plets (i.e. supersymmetry is not invoked), which involve in addition right handed neutrinos…
In supersymmetric theories with R-parity breaking, trilinear couplings of two leptons to scalar sleptons are possible. In electron-positron collisions such interactions would manifest themselves through contact terms in Bhabha scattering…
A model is proposed in which quarks, leptons and perhaps gauge bosons are composites of magnetically charged rishons T(q=1/3) and V(q=0) with magnetic charges g=(1,2,-3)g0. Structural formulas of composite particles and their interactions…
In this talk, we discuss an attempt to construct a realistic model of the grand gauge-Higgs unification. We investigate a 5D SU(6) grand gauge-Higgs unification model compactified on an orbifold S^1/Z_2. Ordinary quarks and leptons,…
The idea of quark-lepton universality at high energies has been introduced as a natural extension to the standard model. This is achieved by endowing leptons with new degrees of freedom -- leptonic colour, an analogue of the familiar quark…
We construct realistic theories in which the Higgs fields arise from extra dimensional components of higher dimensional gauge fields. In particular, we present a minimal 5D SU(3)_C x SU(3)_W model and a unified 5D SU(6) model. In both cases…
We address dynamical supersymmetry breaking within a N=1 supersymmetric Standard-like Model based on a Z_2 x Z_2 Type IIA orientifold with intersecting D6-branes. The model possesses an additional, confining gauge sector with the USp(2)_A x…