Related papers: Exact noncommutative solitons in p-adic strings an…
We derive a class of solutions to the string sigma-model equations for the closed bosonic string. The tachyon field is taken to form a constant condensate and the beta-function equations at one-loop level are solved for the evolution of the…
We discuss construction of classical time dependent solutions in open string (field) theory, describing the motion of the tachyon on unstable D-branes. Despite the fact that the string field theory action contains infinite number of time…
We find an exact solution, with a nonzero net D-brane charge, in the boundary string field theory of brane-anti-brane pairs on a torus. We explicitly take the T-dual of this configuration. The Nahm-transformation of the instantons is…
The amplitudes for the tree-level scattering of the open string tachyons, generalised to the field of p-adic numbers, define the p-adic string theory. There is empirical evidence of its relation to the ordinary string theory in the p_to_1…
We extend earlier ideas about the appearance of noncommutative geometry in string theory with a nonzero B-field. We identify a limit in which the entire string dynamics is described by a minimally coupled (supersymmetric) gauge theory on a…
We address the conjecture that at the tachyonic vacuum open strings get transformed into closed strings. We show that it is possible in the context of boundary string field theory to interpolate between the conventional open string theory,…
On a noncommutative space of rank-1, we construct a codimension-one soliton explicitly and, in the context of noncommutative bosonic open string field theory, identify it with the D24-brane. We compute the tension of the proposed D24-brane,…
In a linear dilaton background, it has been argued that an unstable D-brane can decay to the tachyon vacuum without leaving behind a remnant of tachyon matter. Here we address the question of how the D-brane can decay to the tachyon vacuum…
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 review recent developments of soliton theories and integrable systems on noncommutative spaces. The former part is a brief review of noncommutative gauge theories focusing on ADHM construction of noncommutative instantons. The latter…
We apply a non-linear matrix transformation of Lie-Backlund type on a seed soliton configuration in order to obtain a new solitonic solution in the framework of the 5D low-energy effective field theory of the bosonic string. The seed…
We construct Dp-branes in bosonic string theory as unstable lumps in a truncated string field theory of open strings on a D25-brane. We find that the lowest level truncation gives good quantitative agreement with the predicted D-brane…
We compute, on the disk, the non-linear tachyon $\beta$-function, $\beta^T$, of the open bosonic string theory. $\beta^T$ is determined both in an expansion to the third power of the field and to all orders in derivatives and in an…
We consider tachyon condensation between a D-brane and an anti-D-brane in superstring theory, when they are separated in their common transverse directions. A simple rolling tachyon solution, that describes the time evolution of the…
CFT construction of S-branes describing the rolling and bouncing tachyons is analyzed in the context of a $\theta$-noncommutative deformation of minisuperspace. Half s-brane and s-brane in the noncommutative minisuperspace are analyzed and…
We study how the effect of closed-string tachyon condensation can enter into the on-shell effective action of open-string tachyons in the bosonic case. We also consider open-string one-loop quantum corrections to the on-shell action. We use…
Recently, Hellerman and Schnabl considered the dynamics of unstable D-branes in the background of a linear dilaton. Remarkably, they were able to construct light-like tachyon solutions which interpolate smoothly between the perturbative and…
We discuss origin of equivalence between noncommutative and ordinary Yang-Mills from point of view of string theory. Working in BRST/Hamiltonian framework first we investigate string model in the decoupling limit and show that change of…
The Seiberg-Witten limit of fermionic N=2 string theory with nonvanishing B-field is governed by noncommutative self-dual Yang-Mills theory (ncSDYM) in 2+2 dimensions. Conversely, the self-duality equations are contained in the equation of…
We show that the one loop amplitudes of open and closed string theory in a constant background two-form tensor field are characterized by an effective string tension larger than the fundamental string tension, and by the appearance of…