A ratio ergodic theorem for multiparameter non-singular actions
نویسندگان
چکیده
منابع مشابه
A Ratio Ergodic Theorem for Multiparameter Non-singular Actions
We prove a ratio ergodic theorem for non-singular free Z and R actions, along balls in an arbitrary norm. Using a Chacon-Ornstein type lemma the proof is reduced to a statement about the amount of mass of a probability measure that can concentrate on (thickened) boundaries of balls in R. The proof relies on geometric properties of norms, including the Besicovitch covering lemma and the fact tha...
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ژورنال
عنوان ژورنال: Journal of the European Mathematical Society
سال: 2010
ISSN: 1435-9855
DOI: 10.4171/jems/201