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arXiv · 2607.11616

An exotic Denjoy example of class $C^1$

Maximiliano Escayola
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Abstract

We construct a $C^1$-diffeomorphism of the circle having an invariant Cantor minimal set such that, when the lengths of the connected components of its complement are arranged in decreasing order, the ratios of consecutive lengths do not converge to 1. This gives a negative answer to a longstanding question posed by Dusa McDuff.

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Maximiliano Escayola. 2026-07-13. An exotic Denjoy example of class $C^1$. https://arxiv.org/abs/2607.11616

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