Abstract
Representation theory of CM (=Cohen-Macaulay) modules were initiated by
Auslander-Reiten. The stable categories of CM modules were recently studied
by many people as singular derived categories (Goresntein case) and as stable
categories of matrix factorizations (hypersurface case). I will explain their
properties in the context of tilting theory as well as cluster tilting theory.
In particular we will see that the stable categories of graded (resp. ungraded)
CM modules are often realized as derived (resp. cluster) categories of certain
algebras by using tilting (resp. cluster tilting) theory.