Non-Cohen-Macaulay invariant rings of infinite groups

[摘要] We give explicit examples of invariant rings that are not Cohen-Macaulay for all classical groups SLn (K), GL(n) (K), Sp(2n) (K), SOn (K) and O-n (K), where K is an algebraically closed field of positive characteristic. We prove that every non-trivial unipotent group over K has representations such that the invariant ring is not Cohen-Macaulay. (c) 2006 Elsevier Inc. All rights reserved.

[发布日期] 2006-12-15