Related papers: U(1) gauge invariance from open string field theor…
A discrete symmetry of the string field tachyon condensate noted by Hata and Shinohara is identified as a discrete subgroup of an SU(1,1) symmetry acting on the ghost coordinates. This symmetry, known from early studies of free gauge…
The gauge invariance of open string field theory is considered from the point of view of level truncation, and applications to the tachyon condensation problem are discussed. We show that the region of validity of Feynman-Siegel gauge can…
We explored a variety of brane configurations in our previous paper within the two derivative truncation of the unstable D9-brane effective theory. In this paper we extend our previous results with emphasis on the inclusion of the higher…
An appropriate field configuration in non-polynomial closed string field theory is shown to correspond to a general off-shell field configuration in low energy effective field theory. A set of string field theoretic symmetries that act on…
We develop efficient algorithms for level-truncation computations in open bosonic string field theory. We determine the classical action in the universal subspace to level (18,54) and apply this knowledge to numerical evaluations of the…
The open string tachyon and U(1) gauge field as longitudinal fluctuations and the velocity as transverse fluctuation of an arbitrary dimensional D-brane are considered as boundary deformations of a closed superstring free action. The path…
We construct a system of bosonic closed string field theory coupled to a D-brane. The interaction between the D-brane and closed string field is introduced using the boundary state which is a function of constant field strength $F_{\mu\nu}$…
Certain configurations of D-branes, for example wrong dimensional branes or the brane-antibrane system, are unstable to decay. This instability is described by the appearance of a tachyonic mode in the spectrum of open strings ending on the…
In the cubic string field theory, using the gauge invariant operators corresponding to the on-shell closed string vertex operators, we have explicitly evaluated the decay amplitudes of two open string tachyons or gauge fields to one closed…
We discuss the problem of tachyon condensation in the framework of background independent open string field theory. We show, in particular, that the computation of the string field theory action simplifies considerably if one looks at…
We propose a systematic procedure for extracting gauge invariant and gauge fixed actions for various higher-spin gauge field theories from covariant bosonic open string field theory. By identifying minimal gauge invariant part for the…
The level truncation approach to string field theory is used to study the zero-momentum action for vector excitations on a bosonic D-brane which has been annihilated by tachyon condensation. It is shown that in the true vacuum the…
At the final stage of unstable D-brane decay in the effective field theory approach, all energy and momentum of the initial state are taken up by two types of fluids, known as string fluid and tachyon matter. In this note, we compare motion…
We improve the study of the lack of perturbative unitarity of noncommutative space-time quantum field theories derived from open string theory in electric backgrounds, enforcing the universality of the mechanism by which a tachyonic branch…
We discuss UV/IR mixing effects in non-supersymmetric non-commutative U(N) gauge theories. We show that the singular (non-planar) terms in the 2- and 3-point functions, namely the poles and the logarithms, can be obtained from a manifestly…
We examine the fluctuations around a Dp-brane solution in an unstable D-brane system using boundary states and also boundary string field theory. We show that the fluctuations correctly reproduce the fields on the Dp-brane. Plugging these…
We study some properties of the tachyonic lumps in the level truncation scheme of bosonic cubic string field theory. We find that several gauges work well and that the size of the lump as well as its tension is approximately independent of…
In this paper, we investigate the localization of the $U(1)$ gauge field on Randall-Sundrum-like braneworld models. The localization of the $U(1)$ gauge field is important because it plays a fundamental role in the branworld theories. To…
Assuming that around the tachyon vacuum the kinetic term of cubic open string field theory is made purely of ghost operators we are led to gauge invariant actions which manifestly implement the absence of open string dynamics around this…
We find an interesting connection between perturbative large N gauge theory and closed superstrings. The gauge theory in question is found on N D3-branes placed at the tip of the cone R^6/Gamma. In our previous work we showed that, when the…