The Prym-Hitchin Connection and Anti-Invariant Level-Rank Duality
Thomas Baier, Michele Bolognesi, Johan Martens, Christian Pauly
TL;DR
The paper extends Hitchin’s non-abelian theta framework to higher-rank Prym varieties arising from unramified double covers, constructing a Prym-Hitchin flat projective connection on bundles of non-abelian theta functions. It develops the geometry of higher-rank anti-invariant Prym moduli, proves key codimension and cohomology results to support the heat-operator construction, and derives a Prym–Hitchin symbol that yields a flat connection. A Prym analogue of Laszlo’s theorem is established, linking the Prym–Hitchin connection with a twisted WZW connection, and the authors formulate and verify an anti-invariant level-rank duality, proving it at level one and showing flatness across all levels via conformal-embedding techniques. The results provide a robust framework for understanding dualities and flat structures in Prym settings, with potential implications for the monodromy and geometric representation theory in non-abelian theta contexts.
Abstract
We construct a "Hitchin-type" connection on bundles of non-abelian theta functions on higher-rank Prym varieties, for unramified double covers of curves. We formulate a version of level-rank duality in this Prym setting (building on work of Zelaci), show it holds for level one, and establish that the duality respects the flat connections at all levels.
