Modular parametrization as Polyakov path integral: cases with CM elliptic curves as target spaces

Abstract

For an elliptic curve $E$ over an abelian extension $k/K$ with CM by $K$ of Shimura type, the L-functions of its $[k:K]$ Galois representations are Mellin transforms of Hecke theta functions; a modular parametrization (surjective map) from a modular curve to $E$ pulls back the $1$-forms on $E$ to give the Hecke theta functions. This article refines the study of our earlier work and shows that certain class of chiral correlation functions in Type II string theory with $[E]_\mathbb{C}$ ($E$ as real analytic manifold) as a target space yield the same Hecke theta functions as objects on the modular curve. The Kähler parameter of the target space $[E]_\mathbb{C}$ in string theory plays the role of the index (partially ordered) set in defining the projective/direct limit of modular curves.