Operations on Cyclic Homology, the X Complex, and a Conjecture of Deligne

Abstract

The goal of this article is to relate recent developments in cyclic homology theory with the theory of operads and homotopical algebra, and hence to provide a general framework to define and study operations in cyclic homology theory.

One crucial new reference is added. Comments in the introduction about the previous attempts to prove Deligne's conjecture is corrected. To appear in Communications in Mathematical Physics. This is a mildly revised version of the original preprint that was announced on December 1996