Some simple C*-Algebras Constructed As Crossed Products with Discrete Outer Automorphism Groups

Abstract

An analogue for C*-algebras is given of the theorem of von Neumann (Theorem VIII of [24]) that the crossed product of a commutative von Neumann algebra by a discrete group acting freely and ergodically is a factor. The method of proof also works for certain noncommutative C*-algebras, and so in these cases one obtains also an analogue of Kallman's noncommutative generalization of von Neumann's theorem (3.3 of [18]). © 1980, Research Institute for Mathematical Sciences. All rights reserved.