Marginal Deformations and Closed String Couplings in Open String Field Theory

TL;DR

This paper explores analytic solutions in open string field theory related to marginal operators, demonstrating their connection to marginal deformations in conformal field theory and analyzing the coupling with closed string states.

Contribution

It provides a detailed analysis of classical solutions constructed from marginal operators and confirms their correspondence to marginal deformations in conformal field theory.

Findings

Couplings exhibit periodic behavior consistent with marginal boundary deformations.

Solutions correspond to marginal deformations in conformal field theory.

Analytic classical solutions constructed from marginal operators are validated.

Abstract

We investigate analytic classical solutions in open string field theory which are constructed in terms of marginal operators. In the classical background, we evaluate a coupling between an on-shell closed string state and the open string field. The resulting coupling exhibits periodic behavior as expected from the marginal boundary deformation of background Wilson lines or a marginal tachyon lump. We confirm that the solutions in open string field theory correspond to a class of marginal deformations in conformal field theory.