Related papers: Supersymmetric Composite Models on Intersecting D-…
We explore models where single new exotic states interact with the Standard Model through an asymmetric Standard Model portal with couplings to at least one quark and one lepton. All effective operators up to dimension six where such…
We present a composite model of quarks with `effective supersymmetry'. The model is based on the gauge group $(SU(2)_S \times SU(2)_M) \times (SU(2)_U \times SU(2)_C \times SU(2)_T) \times SU(5)_{SM}$, where $SU(5)_{SM}$ is the standard…
We propose a E_6 inspired supersymmetric model with a non-Abelian discrete flavor symmetry (S_4 group); that is, SU(3)_c x SU(2)_W x U(1)_Y x U(1)_X x S_4 x Z_2. In our scenario, the additional abelian gauge symmetry; U(1)_X, not only…
We construct an MSSM-like model via Pati-Salam from intersecting D-branes in Type IIA theory on the $\Z_2 \times \Z_2'$ orientifold where the D-branes wrap rigid 3-cycles. Because the 3-cycles are rigid, there are no extra massless fields…
We have constructed all the three-family ${\cal N} = 1$ supersymmetric Pati-Salam models from intersecting D6-branes, and obtained 33 independent models in total. But how to realize the string-scale gauge coupling relations in these models…
We propose a method for constructing pairs of nonsupersymmetric gauge theories related by S-duality. Starting from a known S-duality of supersymmetric theories realized on the worldvolume of D3 branes in type IIB string theory, a new…
We construct intersecting D5-brane orbifold models that yield the (non-supersymmetric) standard model up to vector-like matter and charged-singlet scalars. The models are constrained by the requirement that twisted tadpoles cancel, and that…
We show that more than two generations of quarks and leptons are required to have an anomaly free discrete R-symmetry larger than R-parity, provided that the supersymmetric Standard Model can be minimally embedded into a grand unified…
We propose a minimal embedding of the Standard Model spectrum in a D-brane configuration of type I string theory. The SU(3) color and SU(2) weak interactions arise from two different collections of branes. The model is neither grand unified…
We construct a minimal example of a supersymmetric grand unified model in a toroidal compactification of type I string theory with magnetized D9-branes. All geometric moduli are stabilized in terms of the background internal magnetic fluxes…
The doublet--triplet mass splitting problem is one of the most serious problems in supersymmetric grand unified theories (GUTs). A class of models based on a product gauge group, such as the SU(5)_{GUT} times U(3)_H or the SU(5)_{GUT} times…
In this review we describe the general geometrical framework of brane world constructions in orientifolds of type IIA string theory with D6-branes wrapping 3-cycles in a Calabi-Yau 3-fold. These branes generically intersect in points on the…
We describe a realistic, renormalizable, supersymmetric ``quindecuplet'' model in which the top quark, left handed bottom quark, and up-type Higgs boson are composite, with a compositeness scale $\sim 1-3$ TeV. The top-Higgs Yukawa coupling…
D6-branes intersecting at angles allow for phenomenologically appealing constructions of four dimensional string theory vacua. While it is straightforward to obtain non-supersymmetric realizations of the standard model, supersymmetric and…
A fermion-boson-type Composite Model is proposed. Elementary fields are only one kind of spin-1/2 and spin-0 {\bf preon}. Both are in the global supersymmetric pair with the common electric charge of e/6 and belong to the fundamental…
We construct a model of quark and lepton compositeness based on an $SU(15)$ gauge interaction that confines chiral preons, which are also charged under the weakly-coupled $SU(4)_{\rm PS} \times SU(2)_L\times SU(2)_R$ gauge group. The…
Building on recent work by N. Arkani-Hamed and the present authors, we construct realistic models that break supersymmetry dynamically and give rise to composite quarks and leptons, all in a single strongly-coupled sector. The most…
We construct a fairy general family of supersymmetric solutions in time- and space-dependent backgrounds in general supergravity theories. One class of the solutions are intersecting brane solutions with factorized form of time- and…
Recently it was shown that, in the framework of superstring inspired $\E$ models, the presence of generation dependent discrete symmetries allows us to construct a phenomenologically viable class of models in which the three generations of…
We propose a theory of quark and lepton mass and mixing with non-universal $Z'$ couplings based on a 5d Standard Model with quarks and leptons transforming as triplets under a new gauged $SO(3)$ isospin. In the 4d effective theory, the…