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Smooth Siegel disks via semicontinuity: a remark on a proof of Buff and Cheritat

Artur Avila
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Abstract

Recently, Xavier Buff and Arnaud Cheritat have provided an elegant proof of the existence of quadratic Siegel disks with smooth boundary. In this short note, we show how results of Yoccoz and Risler can be used to conclude the same result. Our proof is a small modification of the argument given by Buff and Cheritat.

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Artur Avila. 2003-05-19. Smooth Siegel disks via semicontinuity: a remark on a proof of Buff and Cheritat. https://arxiv.org/abs/math/0305272

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