Observables for identity-based tachyon vacuum solutions

TL;DR

This paper develops a modified algebraic framework in string field theory to analytically compute observables like energy and overlaps for identity-based solutions, including the tachyon vacuum.

Contribution

It introduces a modified KBc algebra to evaluate observables analytically for identity-based solutions in string field theory.

Findings

Analytic expressions for energy densities obtained.

Gauge invariant overlaps calculated explicitly.

Results confirm the validity of the modified algebra approach.

Abstract

We consider a modified KBc algebra in bosonic open string field theory expanded around identity-based scalar solutions. By use of the algebra, classical solutions on the background are constructed and observables for them, including energy densities and gauge invariant overlaps, are calculable. These results are applied to evaluate observables analytically for both of the identity-based trivial pure gauge solution and the identity-based tachyon vacuum solution.