Positivity of the Poincaré bundle on the moduli space of vector bundles and its applications

Abstract

We prove that the normalized Poincaré bundle on the moduli space of stable rank r vector bundles with a fixed determinant on a smooth projective curve X induces a family of nef vector bundles on the moduli space. Two applications follow. We show that when the genus of X is large, the derived category of X is embedded into the derived category of the moduli space for arbitrary rank and coprime degree, which extends the results of Narasimhan, Fonarev-Kuznetsov, and Belmans-Mukhopadhyay. As the second application, we construct a family of ACM bundles on the moduli space. A key ingredient of our proof is the investigation of birational geometry of the moduli spaces of parabolic bundles.