Homological Properties of Rings of Functional-Analytic Type

Strong flatness properties are established for a large class of functional-analytic rings including all C*-algebras. This is later used to prove that all those rings satisfy excision in Hochschild and in cyclic homology over almost arbitrary rings of coefficients and that, for stable C*-algebras, the Hochschild and cyclic homology groups defined over an arbitrary coefficient ring$k \subset \mathbb{C}$of complex numbers (e.g., k=Z or$\overline{\mathbb{Q}}$) vanish in all dimensions.