Related papers: More about the Standard Model at Intersecting Bran…
We consider the interactions between Dp-branes intersecting at an arbitrary number of angles in the context of type II string theory. For cosmology purposes we concentrate in the theory on R^{3,1} x T^6. Interpreting the distance between…
BPS configurations of intersecting branes have many applications in string theory. We attempt to provide an introductory and pedagogical review of supergravity solutions corresponding to orthogonal BPS intersections of branes with an…
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…
It is well known that D-brane instantons can generate contributions to the effective superpotential of gauge theories living on D-branes which are perturbatively forbidden by global U(1) symmetries. We extend this idea to theories with…
A review of supersymmetry theory and phenomenology is presented. Topics discussed include: gravity-mediated (SUGRA) and gauge-mediated (GMSB) supersymmetry breaking models; an overview of non-universal soft-supersymmetry-breaking masses and…
We generalize the ISS model of spontaneous supersymmetry breaking to lower dimensions. We also comment on the dynamics of the corresponding brane systems in string theory, and on possible applications to gauge/gravity duality.
We present a consistent string theory model which reproduces the Standard Model, consisting of a D3-brane at a simple orbifold singularity. We study some simple features of the phenomenology of the model. We find that the scale of stringy…
We address dynamical supersymmetry breaking within a N=1 supersymmetric Standard-like Model based on a Z_2 x Z_2 Type IIA orientifold with intersecting D6-branes. The model possesses an additional, confining gauge sector with the USp(2)_A x…
Most phenomenological models of supersymmetry breaking rely on nonzero F-terms rather than nonzero D-terms. An important reason why D-terms are often neglected is that it turns out to be very challenging to realize D-terms at energies…
In particle physics model building discrete symmetries are often invoked to forbid unwanted or dangerous couplings. A classical example is the R-parity of the MSSM, which guarantees the absence of dimension four baryon- and lepton-number…
I discuss several aspects of strings as unified theories. After recalling the difficulties of the simplest supersymmetric grand unification schemes I emphasize the distinct features of string unification. An important role in constraining…
By employing D6-branes intersecting at angles in $D = 4$ type I strings, we construct {\em five stack} string GUT models (PS-II class), that contain at low energy {\em exactly the Standard model} with no extra matter and/or extra gauge…
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…
The particle spectrum of the supersymmetric extension of the standard model with a gauge singlet is studied. Soft supersymmetry breaking terms are explicitly chosen to be non-universal according to orbifold string theory. they depend on…
We consider a scenario in which Supersymmetry breaking is communicated to the MSSM fields through the interplay of yukawa and gauge interactions. The MSSM spectrum resembles that of split SUSY scenarios, but on top of that it develops some…
We describe the construction of configurations of D6-branes wrapped on compact 3-cycles intersecting at points in non-compact Calabi-Yau threefolds. Such constructions provide local models of intersecting brane worlds, and describe sectors…
The string duality revolution calls into question virtually all of the working assumptions of string model builders. A number of difficult questions arise. I use fractional charge as an example of a criterion which one would hope is robust…
We present a general rule determining how extremal branes can interesect in a configuration with zero binding energy. The rule is derived in a model independent way and in arbitrary spacetime dimensions $D$ by solving the equations of…
A brief review is given of the ways of testing SUGRA unified models and a class of string models using data from precision electroweak experiments, Yukawa unification constraints, and constraints from dark matter experiments. Models…
We use rotation of one D-brane with respect to the other to reveal the hidden structure of D-branes in type-II theories. This is done by calculation of the interaction amplitude for two different parallel and angled branes. The analysis of…