Tachyon Vacuum in Cubic Superstring Field Theory

TL;DR

This paper presents an exact analytic solution for tachyon condensation in cubic superstring field theory, confirming the tachyon vacuum's existence and reproducing the D-brane tension, with implications for BPS D-branes.

Contribution

It provides the first exact analytic tachyon vacuum solution in modified cubic superstring field theory, demonstrating the absence of cohomology and correct D-brane tension.

Findings

Confirmed the existence of a tachyon vacuum in the theory.

Reproduced the correct D-brane tension.

Found the solution vanishes in the GSO(-) sector, even for BPS D-branes.

Abstract

In this paper we give an exact analytic solution for tachyon condensation in the modified (picture 0) cubic superstring field theory. We prove the absence of cohomology and, crucially, reproduce the correct value for the D-brane tension. The solution is surprising for two reasons: First, the existence of a tachyon vacuum in this theory has not been definitively established in the level expansion. Second, the solution {\it vanishes} in the GSO$(-)$ sector, implying a ``tachyon vacuum'' solution exists even for a {\it BPS} D-brane.