D-branes and boundary states in closed string theories

We give a pedagogical introduction to string theory, D-branes and p-brane solutions.

In this set of lectures various properties of D-branes are discussed. After reviewing the basics, we discuss unstable D-brane/anti-D-brane systems, a subject pioneered by Sen. Following him, we discuss the construction of the non-BPS D0-brane in type I theory. This state is stable since it carries a conserved Z_2 charge. The general classification of D-brane charges using K-theory is discussed. The results for the type I theory, and the T-dual type I' theory, are emphasized. ...

These are a set of lectures presented at the CERN-La Plata-Santiago de Compostella School of Physics, La Plata, May 1997. A brief introduction to the non-perturbative structure of string theory is presented. Various non-perturbative dualities in ten and six dimensions as well as D-branes are discussed.

This thesis first gives a background and review of the article hep-th/0102038, where we substantiated a conjectured duality between two a priori unrelated gauge theories, N=2 quiver theory and N=2 Seiberg-Witten theory. These gauge theories have different realisations as the worldvolume theories on different D-brane configurations. We showed that there is an identity between the spaces of vacua (moduli spaces) arising in the two theories, which suggests that the corresponding...

String theories with branes can often be generalized by adding brane-antibrane pairs. We explore the cancellation of anomalies in this more general context, extending the familiar anomaly-cancelling mechanisms, both for ten-dimensional string theories with D-branes and for certain supersymmetric compactifications.

In this paper we would like to discuss the emergence of D-branes from infinite many D-instantons in bosonic and type IIA string theory in the framework of boundary string field theory.

A brief review of some of the central ideas, terminology and techniques of the technology of orientifolds and D-branes is presented. Some applications are reviewed, including the construction of dual solitonic strings in the context of string/string duality, the computation of the Bekenstein-Hawking entropy/area law for extremal black holes, and the construction of N=1 string vacua in dimensions lower than ten. (Contribution to the proceedings of the fourth International Work...

Boundary states for D-branes are constructed using the light cone gauge. The D-brane breaks half the spacetime supersymmetry giving rise to fermionic zero modes living on the brane. The nonlinear realization of the broken supersymmetry on the open string degrees of freedom is analysed and the influence of boundary terms coming from closed string vertex operators is discussed.

This thesis deals with the two duality symmetries of N=2 D=10 supergravity theories that are descendant from the full superstring theory: fermionic T-duality and U-duality. The fermionic T-duality transformation is applied to the D-brane and pp-wave solutions of type IIB supergravity. New supersymmetric solutions of complexified supergravity are generated. We show that the pp-wave yields a purely imaginary background after two dualities, undergoes a geometric transformation a...

In this paper we construct path integral representations of the boundary states in some special backgrounds such as the U(1) gauge field background, the linear dilaton background and the open string tachyon background. The initial purpose of this paper is to construct a general solution of the boundary conformal field theory with the analytical approach, mainly for the constraint equations$(L_{n}-\tilde{L}_{-n}) |B > =0 $ are difficult to be solved to obtain the solution repr...