Analytic Solution for Tachyon Condensation in Berkovits' Open Superstring Field Theory

TL;DR

This paper provides an analytic solution for tachyon condensation in Berkovits' open superstring field theory, confirming the expected D-brane tension and offering insights into D-brane charge encoding.

Contribution

It introduces a novel analytic solution expressed as matrix products within the star algebra, enabling explicit computation of the nonpolynomial action.

Findings

Solution confirms non-BPS D-brane tension matches Sen's conjecture

All string fields for the action are derived in closed form

Comments on D-brane charge encoding in the tachyon vacuum topology

Abstract

We present an analytic solution for tachyon condensation on a non-BPS D-brane in Berkovits' open superstring field theory. The solution is presented as a product of $2\times 2$ matrices in two distinct $GL_2$ subgroups of the open string star algebra. All string fields needed for computation of the nonpolynomial action can be derived in closed form, and the action produces the expected non-BPS D-brane tension in accordance with Sen's conjecture. We also comment on how D-brane charges may be encoded in the topology of the tachyon vacuum gauge orbit.