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arXiv · 2404.05877

Uniform vector-valued pointwise ergodic theorems for operators

Micky Barthmann·Sohail Farhangi
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Abstract

We prove a uniform vector-valued Wiener-Wintner Theorem for a class of operators that includes compositions of ergodic Koopman operators with contractive multiplication operators. Our results are new even in the case of complex-valued functions, as they also apply to some non-positive non-contractive operators, and they give new uniform pointwise theorems for ergodic, weakly mixing, and mildly mixing Koopman operators.

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Micky Barthmann, Sohail Farhangi. 2024-04-08. Uniform vector-valued pointwise ergodic theorems for operators. https://doi.org/10.3934/dcds.2025032

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