Twisted Sectors in Calabi-Yau Type Fermat Polynomial Singularities and Automorphic Forms
Dingxin Zhang, Jie Zhou
TL;DR
The paper reveals a deep link between twisted sectors in vanishing cohomology of one-parameter Fermat CY-type singularities and automorphic forms on triangular groups, enabling automorphic interpretations of genus-zero GW invariants for corresponding Fermat CY varieties. It develops a unified D-module and mixed Hodge theoretic framework for geometric sections, showing they become components of automorphic forms under Schwarzian uniformization, and demonstrates this explicitly in Fermat cubic, quartic, and quintic examples. The results connect LG/CY correspondence, period integrals, and mirror symmetry to automorphic structures, and establish that the genus-zero GW I-function is an automorphic form component valued in cohomology for appropriate groups, with special cases yielding elliptic modular forms. A notable contribution is the Yamaguchi–Yau ring for the quintic, shown to be a differential ring of automorphic generators with algebraic independence, which provides new tools for understanding higher-genus GW theory and its modular properties.
Abstract
We study one-parameter deformations of Calabi-Yau type Fermat polynomial singularities along degree-one directions. We show that twisted sectors in the vanishing cohomology are components of automorphic forms for certain triangular groups. We prove consequentially that genus zero Gromov-Witten generating series of the corresponding Fermat Calabi-Yau varieties are components of automorphic forms. The main tools we use are mixed Hodge structures for quasi-homogeneous polynomial singularities, Riemann-Hilbert correspondence, and genus zero mirror symmetry.
