Introduction to Elliptic Quasi-Modular Forms via Moduli Spaces
Walter Andrés Páez Gaviria
TL;DR
The paper develops a framework for elliptic quasi-modular forms through moduli spaces and the Gauss-Manin connection, embedding Ramanujan-type differential relations into a geometric setting via enhanced elliptic curves. It defines the AMSY Gauss-Manin Lie algebra as an $\mathfrak{sl}_2(\mathbb{C})$-action on a moduli space of enhanced elliptic curves and produces explicit Ramanujan vector fields whose pullback recovers $E_2,E_4,E_6$. In the elliptic mirror-symmetry context, genus-$g$ Hurwitz-type counts are organized into partition functions, which reduce to traces of monodromy operators and are amenable to diagonalization by representation-theoretic methods; combining Frobenius theory with a half-integer product expansion yields that the resulting generating functions are quasimodular, with the $m=2$ case explicitly verified. Overall, the work unifies automorphic and topological-string-type objects for elliptic curves, linking Hodge-theoretic variation, modular forms, and Hurwitz-type counts in a coherent GMCD framework.
Abstract
In this paper we present rigorously and as succintly as possible the theory of elliptic quasi-modular forms by means of moduli spaces and the Gauss-Manin connection, and deal with one of the main historical appearances of quasi-modular forms, which was the seminal case of mirror symmetry treated by Dijkgraaf.
