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arXiv · 2011.14278

Nonsingular transformations that are ergodic with isometric coefficients and not weakly doubly ergodic

Beatrix Haddock·James Leng·Cesar E. Silva
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Abstract

We study two properties of nonsingular and infinite measure-preserving ergodic systems: weak double ergodicity, and ergodicity with isometric coefficients. We show that there exist infinite measure-preserving transformations that are ergodic with isometric coefficients but are not weakly doubly ergodic. We also give type $\text{III}_\lambda$ examples of such systems, $0<\lambda\leq 1$. We prove that under certain hypotheses, systems that are weakly mixing are ergodic with isometric coefficients and along the way we give an example of a uniformly rigid topological dynamical system along the sequence $(n_i)$ that is not measure theoretically rigid along $(n_i)$ for any nonsingular ergodic finite measure.

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Beatrix Haddock, James Leng, Cesar E. Silva. 2020-11-29. Nonsingular transformations that are ergodic with isometric coefficients and not weakly doubly ergodic. https://arxiv.org/abs/2011.14278

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