相关论文: Noncommutative Tachyons
We consider an unstable bound system of two supersymmetric Dirichlet branes of different dimensionality ($p,p'$ with $p'<p$) embedded in a flat non-compactified IIA or IIB type background. We study the decay, via tachyonic condensation, of…
The purpose of this talk is to review a few issues concerning noncommutativity arising from String Theory. In particular, it is shown how in Type IIB Theory, the annihilation of a D3-\bar{D3} brane pair yields a D1-string. This object, in…
We find a novel tachyon condensation which provides a D-brane system with spherical worldvolume in the flat spacetime. The tachyon profile is a deformation of a known D0-brane solution on non-BPS D3-branes in type IIA superstring theory,…
Using the techniques of two dimensional conformal field theory we construct time dependent classical solutions in open string theory describing the decay of an unstable D-brane in the presence of background electric field, and explicitly…
We propose an ansatz for the equations of motion of the noncommutative model of a tachyonic scalar field interacting with a gauge field, which allows one to find time-dependent solutions describing decaying solitons. These correspond to the…
The non-commutative geometry of a large auxiliary $B$-field simplifies the construction of D-branes as solitons in open string field theory. Similarly, fundamental strings are constructed as localized flux tubes in the string field theory.…
The U(1) gauge theory on a D3-brane with non-commutative worldvolume is shown to admit BIon-like solutions which saturate a BPS bound on the energy. The mapping of these solutions to ordinary fields is found exactly, namely…
We show that Dirichlet p-brane can be expressed as a configuration of infinitely many Dirichlet (p-2)-branes in the bosonic string theory. Using this fact, we interpret the massless fields on the p-brane worldvolume as deformations of the…
A system of k Neveu-Schwarz (NS) 5-branes of type II string theory with one transverse direction compactified on a circle admits various unstable D-brane systems, - some with geometric instability arising out of being placed at a point of…
We consider how the time-dependent decay process of an unstable D-brane should be described in the full (quantum) open-closed string theory. It is argued that the system, starting from the unstable D-brane configuration, will evolve in time…
It has been shown recently that by turning on a large noncommutativity parameter, the description of tachyon condensation in string theory can be drastically simplified. We reconsider these issues from the standpoint of string field theory,…
It has been conjectured that condensation of tachyons on a bosonic D-brane gives rise to vacuum / soliton solutions which are independent of the initial magnetic field on the D-brane. We present evidence for this conjecture using results…
We review the recent developments in our understanding of non-BPS states and branes in string theory. The topics include 1) construction of unstable non-BPS D-branes in type IIA and type IIB string theories, 2) construction of stable…
In this lecture notes we explain and discuss some ideas concerning noncommutative geometry in general, as well as noncommutative field theories and string field theories. We consider noncommutative quantum field theories emphasizing an…
In these notes we provide a pedagogical introduction to the subject of tachyon condensation in Witten's cubic bosonic open string field theory. We use both the low-energy Yang-Mills description and the language of string field theory to…
This paper is devoted to the construction of stable and unstable Dp-branes in generalized Carroll space-times. We also study tachyon solutions on the world-volume of unstable Dp-brane in Carrollian background and discuss their physical…
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)…
The open string ending on a D-brane with a constant B-field in a pp-wave Ramond-Ramond background is exactly solvable. The theory is controlled by three dimensionful parameters: alpha', the mass parameter (RR background times the lightcone…
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…
We argue that a semi-infinite D6-brane ending on an NS5-brane can be obtained from the condensation of the tachyon on the unstable D9-brane of type IIA theory. The construction uses a combination of the descriptions of these branes as…