Resonance equals reducibility for A-hypergeometric systems
arXiv:1009.3569 · doi:10.2140/ant.2012.6.527
Abstract
Classical theorems of Gel'fand et al., and recent results of Beukers, show that non-confluent Cohen-Macaulay A-hypergeometric systems have reducible monodromy representation if and only if the continuous parameter is A-resonant. We remove both the confluence and Cohen-Macaulayness conditions while simplifying the proof.
9 pages, final version