AUSLANDER’S THEOREM AND N-ISOLATED SINGULARITIES

Abstract

One of the most stunning results in the representation theory of Cohen–Macaulay rings is Auslander’s well-known theorem which states a CM local ring of finite CM type can have at most an isolated singularity. There have been some generalizations of this in the direction of countable CM type by Huneke and Leuschke. In this paper, we focus on a different generalization by restricting the class of modules. Here we consider modules which are high syzygies of MCM modules over noncommutative rings, exploiting the fact that noncommutative rings allow for finer homological behavior. We then generalize Auslander’s theorem in the setting of complete Gorenstein local domains by examining path algebras, which preserve finiteness of global dimension.