IPMU Komaba Seminar

Speaker: Todor Milanov (IPMU)
Title: Quasi-modular forms and Gromov--Witten theory of elliptic orbifold P^1
Date (JST): Mon, Oct 18, 2010, 16:30 - 18:00
Place: Room 002, Mathematical Sciences Building, Komaba Campus
Abstract: This talk is based on my current work with Y. Ruan. Our project is part of the so called Landau--Ginzburg/Calabi-Yau correspondence. The latter is a conjecture, due to Ruan, that describes the relation between the W-spin invariants of a Landau-Ginzburg potential W and the Gromov--Witten invariants of a certain Calabi--Yau orbifold. I am planning first to explain the higher-genus reconstruction formalism of Givental. This formalism together with the work of M. Krawitz and Y. Shen allows us to express the Gromov--Witten invariants of the orbifold P^1's with weights (3,3,3), (2,4,4), and (2,3,6) in terms of Saito's Frobenius structure associated with the simple elliptic singularities P_8, X_9, and J_{10} respectively. After explaining Givental's formalism, my goal would be to discuss the Saito's flat structure, and to explain how its modular behavior fits in the Givental's formalism. This allows us to prove that the Gromov--Witten invariants are quasi-modular forms on an appropriate modular group.