KBc algebra and the gauge invariant overlap in open string field theory

Abstract

\n We study in detail the evaluation of the gauge invariant overlap for analytic solutions constructed out of elements in the $KBc$ algebra in open string field theory. We compute this gauge invariant observable using analytical and numerical techniques based on the sliver frame $\\mathcal{L}_0$ and traditional Virasoro $L_0$ level expansions of the solutions.