Parabolic connections and stack of roots

Abstract

Given a scheme over a field endowed with a strict normal crossings divisor, we define strongly parabolic connections, consistently with the current terminology for Higgs bundles. When the weights are rational with prescribed denominators, we show that strongly parabolic connections correspond to holomorphic connections on the corresponding stack of roots. We use this correspondence to establish that a holomorphic connection on a stack of roots can be reconstructed from its direct image to the moduli space.