Local to global principles for generation time over commutative noetherian rings

Abstract

In the derived category of modules over a commutative noetherian ring a complex $G$ is said to generate a complex $X$ if the latter can be obtained from the former by taking summands and finitely many cones. The number of cones required in this process is the generation time of $X$. In this paper we present some local to global type results for computing this invariant, and discuss applications.

Revision. Incorporate Section 3 into Section 2. To appear in Homology, Homotopy and Applications