Classical Solutions in String Field Theory Around the Tachyon Vacuum

TL;DR

This paper constructs classical solutions in string field theory around the tachyon vacuum that describe D-branes of various dimensions, providing explicit matter states and confirming tension ratios numerically.

Contribution

It introduces a method to find explicit matter states for D-branes of all dimensions in string field theory around the tachyon vacuum.

Findings

Explicit matter states for all D-brane dimensions were derived.

Tension ratios of D-branes match known results within numerical accuracy.

The approach uses a factorized ansatz and solution generating techniques.

Abstract

In a previous paper [hep-th/0012251] we proposed a simple class of actions for string field theory around the tachyon vacuum. In this paper we search for classical solutions describing D-branes of different dimensions using the ansatz that the solutions factorize into the direct product of a matter state and a universal ghost state. We find closed form expressions for the matter state describing D-branes of all dimensions. For the space filling D25-brane the state is the matter part of the zero angle wedge state, the ``sliver'', built in [hep-th/0006240]. For the other D-brane solutions the matter states are constructed using a solution generating technique outlined in [hep-th/0008252]. The ratios of tensions of various D-branes, requiring evaluation of determinants of infinite dimensional matrices, are calculated numerically and are in very good agreement with the known results.