Normal Reflection Subgroups
arXiv:2006.06575
Abstract
We study normal reflection subgroups of complex reflection groups. Our point of view leads to a refinement of a theorem of Orlik and Solomon to the effect that the generating function for fixed-space dimension over a reflection group is a product of linear factors involving generalized exponents. Our refinement gives a uniform proof and generalization of a recent theorem of the second author.
10 pages; to appear in DMTCS Proceedings (Formal Power Series and Algebraic Combinatorics)