相关论文: Standard-like models from D-branes
We discuss the unification of gauge coupling constants in non-supersymmetric open string vacua that possess the properties of Split Supersymmetry, namely the Standard Model with Higgsinos at low energies and where the Standard model…
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…
We study D-branes in a nonsupersymmetric orbifold of type C^2/\Gamma, perturbed by a tachyon condensate, using a gauged linear sigma model. The RG flow has both higgs and coulomb branches, and each branch supports different branes. The…
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 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 derive the rules to construct type IIB compact orientifolds in six and four dimensions including D-branes and anti-D-branes. Even though the models are non-supersymmetric due to the presence of the anti-D-branes, we show that it is easy…
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…
We present a 6D orbifold model on $T^2/\Z2$ which emerges as intermediate step in the compactification of the heterotic string to the supersymmetric standard model in four dimensions. It has $\SU6$ gauge symmetry in the bulk and two pairs…
We consider D4-branes on toric Calabi-Yau spaces. The quiver gauge theory that describes several D4-branes on the Calabi-Yau has a Higgs branch, that describes configurations of a single large D4-brane with the same charges. We propose that…
Based on the low-energy effective field theory of D-branes, the mass spectrum of an extended Standard Model with two-Higgs doublets used to generate all the mass terms is investigated. Besides the gauge bosons, the fermion mass spectrum is…
We present what we believe are the first specific string (D-brane) constructions whose low-energy limit yields just a three generation $SU(3)\times SU(2)\times U(1)$ standard model with no extra fermions nor U(1)'s (without any further…
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…
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…
We present supersymmetric, tadpole-free d=4,N=1 orientifold vacua with a three family chiral fermion spectrum that is identical to that of the Standard Model. Starting with all simple current orientifolds of all Gepner models we perform a…
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…
The success of SU(5)-like gauge coupling unification boundary conditions $g_3^2=g_2^2=5/3 g_1^2$ has biased most attempts to embed the SM interactions into a unified structure. After discussing the limitations of the orthodox approach, we…
Type I string theory provides eight classes of unstable D-brane systems. We determine the gauge group and tachyon spectrum for each one, and thereby describe the gauge symmetry breaking pattern in the low-energy world-volume 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)…
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…
Four stacks of intersecting supersymmetric fractional D6-branes on the Z_6' orientifold have previously been used to construct consistent models having the spectrum of the supersymmetric Standard Model, including a single pair of Higgs…