Stiffness of finite free resolutions and the Canonical Element Conjecture

Abstract

Over a noetherian local ring certain minimal finite free resolutions possess a property which we call stiffness. This calls to mind the Buchsbaum-Eisenbud criterion for exactness. Yet we only prove stiffness over equicharacteristic rings. However, Hochster's Canonical Element Conjecture is shown to be true for every ring with a fixed prime residual characteristic, precisely when every resolution over each Gorenstein ring of this type is stiff.