Field Redefinitions, T-duality and Solutions in Closed String Field Theories

TL;DR

This paper explores classical solutions in closed string field theories, examining how field redefinitions and T-duality relate solutions in string field theory to those in low-energy effective theories, confirming their consistency.

Contribution

It demonstrates how T-duality can determine field redefinitions connecting string field solutions to effective theory solutions, especially for massless fields.

Findings

Massless solutions are uncorrected and match known solutions like the chiral null model and pp-wave.

T-duality helps determine field redefinitions independently of interaction details.

Solutions in effective theories are reproduced from string field theory solutions after redefinition.

Abstract

We investigate classical solutions in closed bosonic string field theory and heterotic string field theory that are obtained order by order starting from solutions of the linearized equations of motion, and we discuss the ``field redefinitions'' which relate massless fields in the string field theory side and the low energy effective theory side. Massless components of the string field theory solutions are not corrected and from them we can infer corresponding solutions in the effective theory: the chiral null model and the pp-wave solution with B-field, which have been known to be alpha'-exact. These two sets of solutions in the two sides look slightly different because of the field redefinitions. It turns out that T-duality is a useful tool to determine them: We show that some part of the field redefinitions can be determined by using the correspondence between T-duality rules in the two sides, irrespective of the detail of the interaction terms and the integrating-out procedure. Applying the field redefinitions, we see that the solutions in the effective theory side are reproduced from the string field theory solutions.