Tachyon solutions in boundary and cubic string field theory

TL;DR

This paper constructs and compares time-dependent tachyon solutions in open and boundary string field theories, revealing their relationships and oscillatory behaviors in bosonic and supersymmetric contexts.

Contribution

It introduces new rolling tachyon solutions in both OSFT and BSFT, and explores their connections, especially the role of the parameter r in linking solutions across theories.

Findings

Recovered oscillating solutions in supersymmetric OSFT.

Established the relation between bosonic OSFT and boundary solutions at specific parameter values.

Identified the conditions under which wild oscillations occur in both theories.

Abstract

We construct rolling tachyon solutions of open and boundary string field theory (OSFT and BSFT, respectively), in the bosonic and supersymmetric (susy) case. The wildly oscillating solution of susy OSFT is recovered, together with a family of time-dependent BSFT solutions for the bosonic and susy string. These are parametrized by an arbitrary constant r involved in solving the Green equation of the target fields. When r=0 we recover previous results in BSFT, whereas for r attaining the value predicted by OSFT it is shown that the bosonic OSFT solution is the derivative of the boundary one; in the supersymmetric case the relation between the two solutions is more complicated. This technical correspondence sheds some light on the nature of wild oscillations, which appear in both theories whenever r>0.