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arXiv · 2604.13802

On the Rokhlin lemma for infinite measure-preserving bijections

Fabien Hoareau·François Le Maître
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Abstract

We study the Rokhlin lemma in the context of infinite measure-preserving bijections, and completely classify such bijections up to $\lambda$-approximate conjugacy, where $\lambda$ is the infinite measure which is preserved. This sharpens the classical version of the Rokhlin lemma, which only provides such a classification up to $\mu$-approximate conjugacy where $\mu$ is a probability measure equivalent to $\lambda$.

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Fabien Hoareau, François Le Maître. 2026-04-15. On the Rokhlin lemma for infinite measure-preserving bijections. https://arxiv.org/abs/2604.13802

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