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Convergence and divergence of ergodic averages

Published online by Cambridge University Press:  19 September 2008

Roger L. Jones
Affiliation:
Department of Mathematics, DePaul University, 2219 N. Kenmore, Chicago, IL 60614, USA
Mate Wierdl
Affiliation:
Department of Mathematics, Northwestern University, Evanston, IL 60201, USA

Abstract

In this paper we consider almost everywhere convergence and divergence properties of various ergodic averages. A general method is given which can be used to construct averages for which a.e. convergence fails, and to show divergence (and in some cases ‘strong sweeping out’) for large classes of ergodic averages. We also show that there are sequences with the gaps between successive terms converging to zero, but such that the Cesaro averages obtained by sampling a flow along these sequences of times converge a.e. for all fL1(X).

Type
Research Article
Copyright
Copyright © Cambridge University Press 1994

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