Non-ergodic actions, cocycles and superrigidity

Abstract

This paper proves various results concerning non-ergodic actions of locally compact groups and particularly Borel cocycles defined over such actions. The general philosophy is to reduce the study of the cocycle to the study of its restriction to each ergodic component of the action, while being careful to show that all objects arising in the analysis depend measurably on the ergodic component. This allows us to prove a version of the superrigidity theorems for cocycles defined over non-ergodic actions.

References in corpus (1)

• Local Rigidity for Cocycles

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• Equivariant maps for measurable cocycles with values into higher rank Lie groups
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