相关论文: Non-supersymmetric D-Brane Configurations with Bos…

This is the first of a series of three papers on open string field theories based on Witten star product deformed with a gauge invariant open/closed coupling. This deformation is a tree-level tadpole which destabilizes the initial…

We construct non-supersymmetric four dimensional gauge theories arising as effective theories of D-branes placed on various singularities in Type 0B string theory. We mostly focus on models which are conformal in the large N limit and…

The recently found non-critical open string theories is reviewed. These open strings, noncommutative open string theories (NCOS), arise as consistent quantum theories describing the low energy theory of D-branes in a background electric…

In a tachyon model proposed by Minahan and Zwiebach and derived in the boundary string field theory, we construct various new solutions which correspond to nontrivial brane configurations in string theory. Our solutions include Dp-D(p-2)…

We show that unstable D-branes play the role of ``D-sphalerons'' in string theory. Their existence implies that the configuration space of Type II string theory has a complicated homotopy structure, similar to that of an infinite…

We derive compact expressions for one-loop scattering amplitudes of four open-string vector bosons around supersymmetric configurations with intersecting or magnetized D-branes on toroidal orbifolds. We check the validity of our formulae…

D-branes intersecting at an arbitrary fixed angle generically constitute a configuration unstable toward recombination. The reconnection of the branes nucleates at the intersection point and involves a generalization of the process of brane…

We investigate non-commutativity of open strings, attached to a D$p$-brane, in the presence of the linear dilaton, tachyon, U(1) gauge field as well as constant anti-symmetric $B$-field backgrounds. Non-commutativity parameter, open string…

We investigate spectrum of open strings on D-branes after tachyon condensation in bosonic string theory. We calculate 1-loop partition function of the string and show that its limiting forms coincide with partition functions of open strings…

We consider unstable D0-branes of two dimensional string theory, described by the boundary state of Zamolodchikov and Zamolodchikov [hep-th/0101152] multiplied by the Neumann boundary state for the time coordinate $t$. In the dual…

In this paper we extend the boundary string field theory action for a non-BPS D-brane to the one including the target space fermions and the nonlinear supersymmetry with 32 supercharges up to some order. This is based on the idea that the…

We investigate the open string modes, describing the world-volume of a D p-brane, for its cyclic symmetry in presence of a magnetic field. It is argued that the constant coordinate modes receive non-perturbative correction. We show that…

We formulate and study a class of massive N=2 supersymmetric gauge field theories coupled to boundary degrees of freedom on the strip. For some values of the parameters, the infrared limits of these theories can be interpreted as open…

Studying dynamics of open strings attached to a D2-brane in a NS two form field background, we find that these open strings act as dipoles of U(1) gauge field of the brane. This provides an string theoretic description of the flux…

A construction of compact tachyon-free orientifolds of the non-supersymmetric Type 0B string theory is presented. Moreover, we study effective non-supersymmetric gauge theories arising on self-dual D3-branes in Type 0B orbifolds and…

A generalization of the Maldacena conjecture asserts that Type IIB string theory on $\S^5/\Z_3$ is equivalent to a certain supersymmetric $SU(N)^3$ gauge theory with bifundamental matter. To test this assertion, we analyze the wrapped…

We study D-branes that preserve a diagonal SL(2) affine Lie algebra in string theory on AdS_3. We find three classes of solutions, corresponding to the following representations of SL(2): (1) degenerate, finite dimensional representations…

We describe the construction of string theory models with semirealistic spectrum in a sector of (anti) D3-branes located at an orbifold singularity at the bottom of a highly warped throat geometry, which is a generalisation of the…

We study various aspects of orientifold projections of Type IIB closed string theory on Gepner points in different dimensions. The open string sector is introduced, in the usual constructive way, in order to cancel RR charges carried by…

In this paper, we consider the D-brane, especially ${\rm D}_-$-brane, in the pp-wave background, which has the eight dynamical and the eight kinematical supercharges. Since the pp-wave background has not a SO(8) but a ${\rm SO}(4) \times…