Quot spaces in tilted hearts and Hall algebra modules

Abstract

We construct a two sided categorical action of the Hall algebra of semistable coherent sheaves of fixed slope on a curve X on the derived category of certain Quot spaces in tilted hearts on X. Following the philosophy in arXiv:2207.08926v2, the action is induced by correspondence stacks that parameterize extensions of such quotients by semistable sheaves. In the process, we compare different moduli spaces on X: Quot spaces, Bradlow pairs, and stable pairs in the sense of arXiv:2207.08926v2.