Related papers: D-branes and the Standard Model
We report on progress towards constructing string models incorporating both realistic D-brane matter content and moduli stabilisation with dynamical low-scale supersymmetry breaking. The general framework is that of local D-brane models…
A recent D-brane model designed to accommodate a phenomenologically acceptable fourth generation of chiral fermions was noted to produce an unexpected additional unbroken nonanomalous U(1) gauge group at the string scale. We show that the…
It has been recently shown that the discrepancy between the theoretical and experimental values of the anomalous magnetic moment of the muon can be fully accommodated by considering the contribution of few Kaluza-Klein (KK) states of the…
Recently we proposed a TeV-scale Supersymmetric Standard Model in which the gauge coupling unification is as precise (at one loop) as in the MSSM, and occurs in the TeV range. One of the key ingredients of this model is the presence of new…
We systematically search intersecting D-brane models, which just realize the Standard Model chiral matter contents and gauge symmetry. We construct new classes of non-supersymmetric Standard Model-like models. We also study gauge coupling…
I briefly describe the recent construction of the first specific string D-brane models yielding just the SM massless fermion spectrum. One of the most remarkable facts predicted by these constructions is that the global symmetries of the SM…
Adjoint supermultiplets (1,3,0) and (8,1,0) modify the evolution of gauge couplings. If the unification of gauge couplings occurs at the string scale, their masses are fixed at around $10^{13}$ GeV. This scale coincides with expected…
This thesis studies meta- and exactly stable supersymmetry breaking mechanisms in heterotic and type IIB string theories and constructs an F-theory Grand Unified Theory model for neutrino physics in which neutrino mass is determined by the…
We point out that models where gauge and charged matter fields live on the world volume of D3 branes can provide a weak string coupling description of the gauge coupling unification in the supersymmetric standard model at a scale of order…
1. Preliminaries. 2. Heterotic string and motivations for large volume compactifications; 2.1 Gauge coupling unification; 2.2 Supersymmetry breaking by compactification. 3. M-theory on S^1/Z_2 \times Calabi-Yau. 4. Type I/I' string theory…
It is known that chiral fermions naturally appear at certain intersections of branes at angles. Motivated by this fact, we propose a string scenario in which different standard model gauge interactions propagate on different (intersecting)…
We construct new D6-brane model vacua (non-supersymmetric) that have at low energy exactly the standard model spectrum (with right handed neutrinos). The minimal version of these models requires five stacks of branes. and the construction…
We explore the possibility of embedding the Pati-Salam model in the context of Type I brane models. We study a generic model with U(4)_C x U(2)_L x U(2)_R gauge symmetry and matter fields compatible with a Type I brane configuration.…
We discuss the phenomenology and cosmology of a Standard-like Model inspired by string theory, in which the gauge fields are localized on D-branes wrapping certain compact cycles on an underlying geometry, whose intersection can give rise…
A three-family non-supersymmetric model with U(3)^3 gauge symmetry is analyzed in the context of intersecting D-branes. This is equivalent to the `trinification' model extended by three U(1) factors which survive as global symmetries in the…
The extended electroweak $\mathrm{SU(3)_c \otimes SU(3)_L \otimes U(1)_X}$ symmetry framework "explaining" the number of fermion families is revisited. While $331$-based schemes can not easily be unified within the conventional field theory…
We construct D=4 Type I vacua with massless content remarkably close to that of the standard model of particle physics. They are tachyon-free non-supersymmetric models which are obtained starting with a standard D=4, N=1 compact Type IIB…
In this note we explore the possibility of obtaining gauge bosons and fermionic spectrum as close as possible to the Standard Model content, by placing D3-branes at a ZN orbifold-like singularity in the presence of D7-branes. Indeed, we…
We construct eight-stack intersecting D5-brane models, with an orbifold transverse space, that yield the (non-supersymmetric) standard model up to vector-like leptons. The matter includes right-chiral neutrinos and the models have the…
Motivated by D-brane scenarios, we consider a non-supersymmetric model based on the gauge symmetry U(3)_CxU(3)_LxU(3)_R$ which is equivalent to the SU(3)^3 ``trinification'' model supplemented by three U(1)s. Two U(1) combinations are…