Related papers: Open Strings on the Neveu-Schwarz Pentabrane

In this paper we show that in some important cases 4-dimensional data can be extracted from superstring theory such that a) the data are 4 Euclidean geometries embedded in standard $\mathbb{R}^{4}$, b) these data depend on NS and D brane…

We construct three dimensional Chern-Simons-matter theories with gauge groups U(N)xU(N) and SU(N)xSU(N) which have explicit N=6 superconformal symmetry. Using brane constructions we argue that the U(N)xU(N) theory at level k describes the…

Extending recent work on SU gauge theory, we engineer local string models for N=1 four-dimensional SO and USp gauge theories coupled to matter in the fundamental. The local models are type IIB orientifolds with D7 branes on a curved…

In this thesis we study string theory with D-branes and possibly orientifolds in curved or time-dependent spaces. Our study aims at understanding some aspects of curved and time-dependent spaces, notably because of their importance in…

In this thesis we discuss non-perturbative phenomena emerging in gauge and in string/supergravity theories. We compute the partition function of 5D minimal supersymmetric U(1) gauge theory with extra adjoint matter in general…

We review recent work identifying soft SUSY-breaking terms in local type II string models with branes and magnetic fluxes. We then make a new observation about the configuration space of D-branes in Calabi-Yau backgrounds, and identify vevs…

Motivated by Ooguri and Vafa, we study superstrings in flat R^4 in a constant self-dual graviphoton background. The supergravity equations of motion are satisfied in this background which deforms the N=2 d=4 flat space super-Poincare…

We describe the general features of the Neveu-Schwarz and Ramond sectors of logarithmic conformal field theories with N=1 supersymmetry. Three particular systems are examined in some detail -- D-brane recoil, a superconformal extension of…

We consider type IIB compactifications on a general 4D group manifold with different types of possible spacetime filling O-planes and the corresponding D-branes parallel to them. Once fluxes allowed by the associated orientifold projection…

It is shown that many of the $p$-branes of type II string theory and $d=11$ supergravity can have boundaries on other $p$-branes. The rules for when this can and cannot occur are derived from charge conservation. For example it is found…

These lectures intend to give a pedagogical introduction into some of the developments in string theory during the last years. They include perturbative T-duality and non perturbative S- and U-dualities, their unavoidable demand for…

We study pairs of planar D-branes intersecting on null hypersurfaces, and other related configurations. These are supersymmetric and have finite energy density. They provide open-string analogues of the parabolic orbifold and null-fluxbrane…

Making use of the N=2 Liouville theory and world-sheet techniques, we study the properties of D-branes wrapped around vanishing SUSY cycles of singular Calabi-Yau n-folds (n=2,3,4). After constructing boundary states describing the wrapped…

The near-horizon region of Neveu-Schwarz fivebranes provides interesting examples of gauge/gravity duality. We revisit the structure of wrapped and/or intersecting fivebranes using the tools of null-gauged WZW models in worldsheet string…

We consider supergravity solutions of D5 branes wrapped on supersymmetric 2-cycles and use them to discuss relevant features of four-dimensional N=1 and N=2 super Yang-Mills theories with gauge group SU(n). In particular in the N=1 case,…

We review for non-experts possible phenomenological scenari in String Theory. In particular we focus on vacuum configurations with intersecting and/or magnetized unoriented D-branes. We will show how a TeV scale tension may be compatible…

The dynamics of a Dp brane can be described either by an open string ending on this brane or by an open D(p - 2) brane ending on the same Dp brane. The ends of the open string couple to a Dp brane worldvolume gauge field while the boundary…

We consider closed string tachyons localized at the fixed points of noncompact nonsupersymmetric orbifolds. We argue that tachyon condensation drives these orbifolds to flat space or supersymmetric ALE spaces. The decay proceeds via an…

We consider NS-NS superstring model with several ``magnetic'' parameters $b_s$ (s=1, ...,N) associated with twists mixing a compact $S^1$ direction with angles in $N$ spatial 2-planes of flat 10-dimensional space. It generalizes the…

We construct two-dimensional N=(2,2) supersymmetric gauge theories with orthogonal and symplectic groups using branes and orientifold planes in Type IIA string theory. A number of puzzles regarding the construction, including the effect of…