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arXiv · 1708.01934

Disjointness for measurably distal group actions and applications

Joel Moreira·Florian K. Richter·Donald Robertson
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Abstract

We generalize Berg's notion of quasi-disjointness to actions of countable groups and prove that every measurably distal system is quasi-disjoint from every measure preserving system. As a corollary we obtain easy to check necessary and sufficient conditions for two systems to be disjoint, provided one of them is measurably distal. We also obtain a Wiener--Wintner type theorem for countable amenable groups with distal weights and applications to weighted multiple ergodic averages and multiple recurrence.

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Joel Moreira, Florian K. Richter, Donald Robertson. 2017-08-06. Disjointness for measurably distal group actions and applications. https://doi.org/10.1017/etds.2022.19

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