Period Integrals of Hypersurfaces via Tropical Geometry

Abstract

Let $\left \{ Z_{t} \right \}_{t}$ be a one-parameter family of complex hypersurfaces of dimension $d \geq 1$ in a toric variety. We compute asymptotics of period integrals for $\left \{ Z_{t} \right \}_{t}$ by applying the method of Abouzaid–Ganatra–Iritani–Sheridan, which uses tropical geometry. As integrands, we consider Poincaré residues of meromorphic $(d+1)$-forms on the ambient toric variety, which have poles along the hypersurface $Z_{t}$. The cycles over which we integrate them are spheres and tori, which correspond to tropical $(0, d)$-cycles and $(d, 0)$-cycles on the tropicalization of $\left \{ Z_{t} \right \}_{t}$, respectively. In the case of $d=1$, we explicitly write down the polarized logarithmic Hodge structure of Kato–Usui at the limit as a corollary. Throughout this article, we impose the assumption that the tropicalization is dual to a unimodular triangulation of the Newton polytope.