Ergodicity and mixing of W*-dynamical systems in terms of joinings
arXiv:0803.2147
Abstract
We study characterizations of ergodicity, weak mixing and strong mixing of W*-dynamical systems in terms of joinings and subsystems of such systems. Ergodic joinings and Ornstein's criterion for strong mixing are also discussed in this context.
v1: 9 pages. v2: Extended by 2 sections (Sections 3 and 5), with small changes/corrections elsewhere and a more descriptive title; 22 pages. v3: Improved results in Sections 4 and 5; 24 pages