Toroidal analogues of the Grothendieck-Springer map

Abstract: We study moduli spaces of objects in the derived category of noncommutative ruled surfaces over orbifold curves to find equivariant deformations of moduli spaces of framed sheaves on equivariant elliptic surfaces. These derived categories are a common generalization of the category of modules of the preprojective algebra and of the category of twisted D-modules over a curve. We show that the birational geometry of the Hilbert scheme of points on an equivariant elliptic surface is controlled by an elliptic root system, and conjecture in general and prove in special cases that moduli spaces of objects in these derived categories provides a deformation of birational models for the Hilbert scheme. We also study the applications of this deformation to the geometric representation theory of the central fiber, specifically to produce geometric correspondences giving rise to Lie algebra actions on the equivariant cohomology of the central fiber and give formulas for the action of the Namikawa-Markman Weyl group of monodromy reflections in terms of this Lie algebra.