Twist Symmetry and Classical Solutions in Open String Field Theory

TL;DR

This paper constructs and analyzes non-twist-invariant classical solutions in open string field theory, revealing their relation to the closed string vacuum and twist symmetry properties.

Contribution

It introduces non-twist-invariant solutions and demonstrates their equivalence to known twist-invariant solutions, expanding understanding of the moduli space and symmetries in open string field theory.

Findings

Solutions become nontrivial at moduli space boundaries

Support for solutions representing the closed string vacuum

Twist invariance persists after background shifts

Abstract

We construct classical solutions of open string field theory which are not invariant under ordinary twist operation. From detailed analysis of the moduli space of the solutions, it turns out that our solutions become nontrivial at boundaries of the moduli space. The cohomology of the modified BRST operator and the CSFT potential evaluated by the level truncation method strongly support the fact that our nontrivial solutions correspond to the closed string vacuum. We show that the nontrivial solutions are equivalent to the twist even solution which was found by Takahashi and Tanimoto, and twist invariance of open string field theory remains after the shift of the classical backgrounds.