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arXiv · 2106.04991

KAM-renormalization and Herman rings for 2D maps

Michael Yampolsky
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Abstract

In this note, we extend the renormalization horseshoe we have recently constructed with N. Goncharuk for analytic diffeomorphisms of the circle to their small two-dimensional perturbations. As one consequence, Herman rings with rotation numbers of bounded type survive on a codimension one set of parameters under small two-dimensional perturbations.

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Michael Yampolsky. 2021-06-09. KAM-renormalization and Herman rings for 2D maps. https://arxiv.org/abs/2106.04991

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