Minimal models for minimal BCOV theories

Abstract

Minimal BCOV theory is a classical field theory which describes a subclass of deformations of the category of perfect complexes on a Calabi-Yau variety. We compute minimal models for $L_\infty$-algebras describing minimal BCOV theory and its variants on flat space and find that they give certain $L_\infty$-extensions of the infinite-dimensional simple Lie superalgebra $\operatorname{SHO}(d|d)$. We apply this computation to compare an $\mathfrak{sl}_2$ action on an odd two-dimensional central extension of $\operatorname{SHO}(3|3)$ first discovered by Kac to an action of $\mathfrak{sl}_2$ on a variant of minimal BCOV theory previously found by the authors.