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arXiv · 1612.02754

On the non-equivalence of the Bernoulli and K properties in dimension four

Adam Kanigowski·Federico Rodriguez-Hertz·Kurt Vinhage
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Abstract

We study skew products where the base is a hyperbolic automorphism of $\mathbb{T}^2$, the fiber is a smooth area preserving flow on $\mathbb{T}^2$ with one fixed point (of high degeneracy) and the skewing function is a smooth non coboundary with non-zero integral. The fiber dynamics can be represented as a special flow over an irrational rotation and a roof function with one power singularity. We show that for a full measure set of rotations the corresponding skew product is $K$ and not Bernoulli. As a consequence we get a natural class of volume-preserving diffeomorphisms of $\mathbb{T}^4$ which are $K$ and not Bernoulli.

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Adam Kanigowski, Federico Rodriguez-Hertz, Kurt Vinhage. 2016-12-08. On the non-equivalence of the Bernoulli and K properties in dimension four. https://arxiv.org/abs/1612.02754

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