Homological mirror symmetry for Milnor fibers via moduli of $A_\infty$-structures

Abstract

We show that the base spaces of the semiuniversal unfoldings of some weighted homogeneous singularities can be identified with moduli spaces of $A_\infty$-structures on the trivial extension algebras of the endomorphism algebras of the tilting objects. The same algebras also appear in the Fukaya categories of their mirrors. Based on these identifications, we discuss applications to homological mirror symmetry for Milnor fibers, and give a proof of homological mirror symmetry for an $n$-dimensional affine hypersurface of degree $n + 2$ and the double cover of the $n$-dimensional affine space branched along a degree $2n + 2$ hypersurface. Along the way, we also give a proof of a conjecture of Seidel from math/0206155 which may be of independent interest.