Rolling down to D-brane and tachyon matter

TL;DR

The paper explores spatially inhomogeneous tachyon decay of unstable D-branes within BSFT. It derives an asymptotic late-time solution in which a kink forms and a surrounding tachyon matter persists with vanishing pressure. The analysis highlights energy localization on the kink and a corresponding brane tension consistent with a lower-dimensional D-brane, while gauge-field excitations are confined to the brane. These results complement conformal field theory approaches and advance the understanding of tachyon condensation in inhomogeneous settings.

Abstract

We investigate the spatially inhomogeneous decay of an unstable D-brane and construct an asymptotic solution which describes a codimension one D-brane and the tachyon matter in boundary string field theory. In this solution, the tachyon matter exists around the lower-dimensional D-brane.