Related papers: Intersecting D-Branes on Shift Z2 x Z2 Orientifold…

We construct and classify categories of D-branes in orientifolds based on Landau-Ginzburg models and their orbifolds. Consistency of the worldsheet parity action on the matrix factorizations plays the key role. This provides all the…

In the noncommutative field theory of open strings in a B-field, D-branes arise as solitons described as projection operators or partial isometries in a $C^*$ algebra. We discuss how D-branes on orbifolds fit naturally into this algebraic…

We identify a deformation of the N=2 supersymmetric sigma model on a Calabi-Yau manifold X which has the same effect on B-branes as a noncommutative deformation of X. We show that for hyperkahler X such deformations allow one to interpolate…

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 study type IIB orientifolds on T^{2d}/Z_N with supersymmetry broken by the compactification. We determine tadpole cancellation conditions including anti-branes and considering different actions for the parity Omega. Using these…

We study the complex deformations of orientifolds of D3-branes at toric CY singularities, using their description in terms of dimer diagrams. We describe orientifold quotients that have fixed lines or fixed points in the dimer, and…

We determine all D-branes in the non-tachyonic 0'B orientifold, examine their world-volume anomalies and study orbifold compactifications. We find that the spectrum of the D-branes contains chiral fermions in the symmetric, antisymmetric…

We study open B-model representing D-branes on 2-cycles of local Calabi--Yau geometries. To this end we work out a reduction technique linking D-branes partition functions and multi-matrix models in the case of conifold geometries so that…

We discuss the appearance of non-supersymmetric D6-brane GUT model constructions. We focus on the construction of the first examples of flipped SU(5) and SU(5) GUTS which have only the SM at low energy. These constructions are based on 4D…

We construct orientifolds of type IIA string theory. The theory is compactified on a T^6/Z_N times Z_M orbifold. In addition worldsheet parity in combination with a reflection of three compact directions is modded out. Tadpole cancellation…

We provide a general overview of the current state of the art in four dimensional three generation model building proposals - using intersecting D-brane toroidal compactifications [without fluxes] of IIA, IIB string theories - which have…

We study D-branes on three-dimensional orbifold backgrounds that admit topologically distinct resolutions differing by flop transitions. We show that these distinct phases are part of the vacuum moduli space of the super Yang-Mills gauge…

We compute the flux induced tadpole and superpotential in various type IIB $Z_N$ compact orientifolds in order to study moduli stabilization. We find supersymmetric vacua with $g_s < 1$ and describe brane configurations with cancelled…

This work discusses string compactifications on the torus with optional Z_4 x Z_4 or Z_2 x Z_2 orbifold action from the perspective of matrix factorizations. The method is brought to a level where model building on these backgrounds is…

We construct a novel orientifold of type IIB string theory that breaks all supersymmetries. It is a closed string theory without open sector and it can be understood as a Scherk-Schwarz deformation in which supersymmetry is restored at…

We study branes and orientifolds on the group manifold of SO(3). We consider particularly the case of the equatorial branes, which are projective planes. We show that a Dirac-Born-Infeld action can be defined on them, although they are not…

We construct D-brane states on an asymmetric orbifold of type IIA on a four-torus, which is modded out by T-duality. We find explicit boundary states charged under the twisted sector gauge fields. Unlike other cases, the boundary states…

Using a ``Superstrings with Torsion'' type description, we study a class of IIB orientifolds in which spacefilling O5 planes and D5 branes wrap the T^2 fiber in a warped modification of the product of 4D Minkowski space and a T^2 fibration.…

Continuing the study in hep-th/0004092 and hep-th/0004092, we investigate a non-trivial string dynamical process related to orientifold planes, i.e., the splitting of physical NS-branes and D(p+2)-branes on orientifold Op-planes. Creation…

We revisit the problem of constructing type IIA orientifolds on T^6/(Z2 x Z2) which admit (non)-factorisable lattices. More concretely, we consider a (Z2 x Z2') orientifold with torsion, where D6-branes wrap rigid 3-cycles. We derive the…