Related papers: Getting just the Standard Model at Intersecting Br…
Intersecting D-brane models seem to be one of the most promising avenues to embed the Standard Model physics within the string context. We review here different aspects of these models. Topics include the question of SUSY and quasi-SUSY in…
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…
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)…
A systematic approach is followed in order to identify realistic D-brane models at toric del Pezzo singularities. Requiring quark and lepton spectrum and Yukawas from D3 branes and massless hypercharge, we are led to Pati-Salam extensions…
Intersecting Dp-branes often give rise to chiral fermions living on their intersections. We study the construction of four-dimensional chiral gauge theories by considering configurations of type II D(3+n)-branes wrapped on non-trivial…
Recent string constructions with intersecting D6 and D5 brane models succeeded in predicting in the low energy limit a symmetry group and a fermionic spectrum similar to that of the SM. In such constructions additional U(1) fields are a…
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 supersymmetric composite models of quarks and leptons from type IIA T^6/(Z_2 x Z_2) orientifolds with intersecting D6-branes. In case of T^6 = T^2 x T^2 x T^2 with no tilted T^2, a composite model of the supersymmetric SU(5)…
The Standard Model indicates the realization of grand unified structures in nature, and can only be viewed as an effective theory below a higher energy cutoff. While the renormalizable Standard Model forbids proton decay mediating operators…
We propose a class of models with gauge mediation of supersymmetry breaking, inspired by simple brane constructions, where R-symmetry is very weakly broken. The gauge sector has an extended N=2 supersymmetry and the two electroweak Higgses…
We analyze the construction of non-supersymmetric three generation six-stack Pati-Salam (PS) $SU(4)_C \times SU(2)_L \times SU(2)_R$ GUT classes of models, by localizing D6-branes intersecting at angles in four dimensional orientifolded…
We introduce a simple scenario where, by starting with a five-dimensional SU(3) gauge theory, we end up with several 4-D parallel branes with localized fermions and gauge fields. Similar to the split fermion scenario, the confinement of…
This thesis is devoted to the study of a class of constructions based on Superstring Theory, baptized in the literature as Intersecting Brane Worlds. In particular we explore several issues regarding the proposal of Intersecting Brane…
The R-symmetry formalism is applied for the supersymmetric economical SU(3)_C X SU(3)_L X U(1)_X (3-3-1) model. The generalization of the minimal supersymmetric standard model relation among R-parity, spin and matter parity is derived, and…
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…
A new supersymmetric standard model based on N=1 supergravity is constructed, aiming at natural explanation for the proton stability without invoking an ad hoc discrete symmetry through R parity. The proton is protected from decay by an…
We propose a bottom-up approach to the building of particle physics models from string theory. Our building blocks are Type II D-branes which we combine appropriately to reproduce desirable features of a particle theory model: 1) Chirality…
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…
We propose a non-universal U(1)'_F symmetry combined with the Minimal Supersymmetric Standard Model. All anomaly cancellation conditions are satisfied without exotic fields other than three right-handed neutrinos. Because our model allows…
Intersecting stacks of supersymmetric fractional branes on the Z_6' orientifold may be used to construct the supersymmetric Standard Model. If a,b are the stacks that generate the SU(3)_{colour} and SU(2)_L gauge particles, then, in order…