On the general action of boundary (super)string field theory

TL;DR

This paper reconstructs boundary superstring field theory using boundary states, simplifies gauge invariance proof, and shows the action's form matches the bosonic case, supporting the conjecture relating it to the disk partition function.

Contribution

It provides a unified formulation of boundary superstring field theory, simplifying the gauge invariance proof and deriving the action without assumptions.

Findings

Action takes the same form as bosonic string field theory.

Gauge invariance proof is simplified using closed string oscillators.

Supports the conjecture relating the action to the disk partition function.

Abstract

We reconstruct boundary superstring field theory via boundary states. After a minor modification of the fermionic two-form, all the equations needed for Batalin-Vilkovisky formulation are simply represented by closed string oscillators and the proof of gauge invariance is drastically simplified. The general form of the action of boundary superstring field theory is also obtained without any assumption and found to take exactly the same form as the bosonic one. As a special case of this action, we revisit the conjecture that the action is simply given by the disk partition function when matter and ghosts are completely decoupled.