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arXiv · 2012.07625

On the projective derivative cocycle for circle diffeomorphisms

Andrés Navas·Mario Ponce
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Abstract

We study the projective derivative as a cocycle of M\"obius transformations over groups of circle diffeomorphisms. By computing precise expressions for this cocycle, we obtain several results about reducibility and almost reducibility to a cocycle of rotations. We also introduce an extension of this cocycle to the diagonal action on the 3-torus for which we generalize the previous results.

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BibTeXRIS

Andrés Navas, Mario Ponce. 2020-12-14. On the projective derivative cocycle for circle diffeomorphisms. https://arxiv.org/abs/2012.07625

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