Related papers: Open string fluctuations around $KBc$ mulibrane ba…
We construct analytic solutions of open string field theory using boundary condition changing (bcc) operators. We focus on bcc operators with vanishing conformal weight such as those for regular marginal deformations of the background. For…
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…
The influence of closed string moduli on the D-brane moduli space is studied from a worldsheet point of view. Whenever a D-brane cannot be adjusted to an infinitesimal change of the closed string background, the corresponding exactly…
It is shown that the topological invariants associated with the two-dimensional world-surface in string theory have nontrivial fluctuations around their nonexistent classical dynamics. Additionally it is proved that the underlying…
Electromagnetic plane waves provide examples of time-dependent open string backgrounds free of $\alpha'$ corrections. The solvable case of open strings in a quadrupolar wave front, analogous to pp-waves for closed strings, is discussed. In…
We construct a class of classical solutions in the Berkovits' open superstring field theory. The resulting solutions correspond to marginal boundary deformations in conformal field theory. The vacuum energy vanishes exactly for the…
Within two specific string cosmology scenarios --differing in the way the pre- and post-big bang phases are joined-- we compute the size and spectral slope of various types of cosmologically amplified quantum fluctuations that arise in…
Recent investigations involving the decay of unstable D-branes in string theory suggest that the tree level open string theory which describes the dynamics of the D-brane already knows about the closed string states produced in the decay of…
We present a series of new gauge invariant quantities in Witten's open string field theory. They are defined for a given set of open string states which satisfy the physical state condition around a classical solution. For known classical…
First we contemplate the operational definition of space-time in four dimensions in light of basic principles of quantum mechanics and general relativity and consider some of its phenomenological consequences. The quantum gravitational…
One of the simplest time-dependent solutions of M theory consists of nine-dimensional Euclidean space times 1+1-dimensional compactified Milne space-time. With a further modding out by Z_2, the space-time represents two orbifold planes…
We present an overview of the intimate relationship between string and D-brane dynamics, and the dynamics of gauge and gravitational fields in three spacetime dimensions. The successes, prospects and open problems in describing both…
We study the boundary state associated with the decay of an unstable D-brane with uniform electric field, 1>e>0 in the string units. Compactifying the D-brane along the direction of the electric field, we find that the decay process is…
We study rigidly rotating strings in the near horizon geometry of the 1+1 dimensional intersection of two orthogonal stacks of NS5-branes, the so called I-brane background. We solve the equations of motion of the fundamental string action…
We construct a class of BRST-invariant closed string states for any classical solution of open string field theory. The closed string state is a nonlinear functional of the open string field and changes by a BRST-exact term under a gauge…
We discuss the integrability of the Berkovits-Siegel open string field equations and derive an infinite set of their non-local (solution-generating) symmetries. The string field equations are embedded in an infinite system of overdetermined…
We present an exact solution of open bosonic string field theory which can be used to describe any time-independent open string background. The solution generalizes an earlier construction of Kiermaier, Okawa, and Soler, and assumes the…
The perturbative analysis of models of open and closed superstrings presents a number of surprises. For instance, variable numbers of antisymmetric tensors ensure their consistency via generalized Green-Schwarz cancellations and a novel…
We consider two Dirichlet p-branes with lower dimensional brane charges and their scattering. We first calculate the cylinder amplitude of open string with suitable boundary conditions. We compare this result with that in the IIB matrix…
We investigate the variation of the string field action under changes of the string field vertices giving rise to different decompositions of the moduli spaces of Riemann surfaces. We establish that any such change in the string action…