Boundary String Field Theory Action Research Articles

Some special features of a rotating-moving Dp-brane

Using the boundary string field theory (BSFT) techniques we study the boundary state and partition function for a dynamical (rotating-moving) Dp-brane coupled to the electromagnetic and tachyonic background fields in superstring theory. By making use of the created partition function, the super BSFT action with a tachyonic field and Dirac-Born-Infeld–type action will be constructed. By analyzing the obtained action interesting features will be revealed.

Homogeneous rolling tachyons in boundary string field theory

Abstract We study decay of a flat unstable D p -brane in the context of boundary string field theory action. Three types of homogeneous rolling tachyons are obtained without and with Born–Infeld type electromagnetic field.

Taming the tachyon in cubic string field theory

We give evidence based on level-truncation computations that the rolling tachyon in cubic open string field theory (CSFT) has a well-defined but wildly oscillatory time-dependent solution which goes as $e^t$ for $t \to -\infty$. We show that a field redefinition taking the CSFT effective tachyon action to the analogous boundary string field theory (BSFT) action takes the oscillatory CSFT solution to the pure exponential solution $e^t$ of the BSFT action.

C= 1 matrix model from string field theory

We show that the boundary string field theory (BSFT) on unstable D0-branes in 2d string theory is equivalent to the double scaled c=1 matrix model (i.e. quadratic action), even though we naively expect many interaction terms in BSFT. It is checked that S-matrices are trivial in the open string theory on the D0-branes. We discuss how to take the closed string decoupling limit in our model in order to make its holographic interpretation clear. We also find some useful lessons from our results in 2d string toward the further understanding of the higher dimensional BSFT action.

Tachyon Matter in Boundary String Field Theory

We analyse the classical decay process of unstable D-branes in superstring theory using the boundary string field theory (BSFT) action. We show that the solutions of the equations of motion for the tachyon field asymptotically approach to T=x^0 and the pressure rapidly falls off at late time producing the tachyon matter irrespective of the initial condition. We also consider the cosmological evolution driven by the rolling tachyon using the BSFT action as an effective action.

A construction of commutative D-branes from Lower dimensional non-BPS D-branes

We construct an exact soliton, which represents a BPS Dp-brane, in a boundary string field theory action of infinitely many non-BPS D(p-1)-branes. Furthermore, we show that this soliton can be regarded as an exact soliton in the full string field theory. The world-volume theory of the BPS Dp-brane constructed in this way becomes usual gauge theory on commutative R^{p+1}, instead of non-commutative plane. We also construct a D$p$-brane from non-BPS D(p-n)-branes by the ABS like configuration. We confirm that the Dp-brane has correct RR charges and the tension.

On the supersymmetry of non-BPS D-brane

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 vacuum with a non-BPS D-brane belongs to the spontaneously broken phase of the supersymmetry. As a result, we find that the action is almost uniquely determined up to the field redefinition ambiguities.