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arXiv · 0707.0075

Herman's Theory Revisited

Konstantin Khanin·Alexey Teplinsky
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Abstract

We prove that a $C^{2+α}$-smooth orientation-preserving circle diffeomorphism with rotation number in Diophantine class $D_δ$, $0<δ<α\le1$, is $C^{1+α-δ}$-smoothly conjugate to a rigid rotation. We also derive the most precise version of Denjoy's inequality for such diffeomorphisms.

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Konstantin Khanin, Alexey Teplinsky. 2007-06-30. Herman's Theory Revisited. https://doi.org/10.1007/s00222-009-0200-z

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