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arXiv · 0909.1015

KAM \`{a} la R

Jürgen Pöschel
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Abstract

Recently R\"ussmann proposed a new new variant of KAM theory based on a slowly converging iteration scheme. It is the purpose of this note to make this scheme accessible in an even simpler setting, namely for analytic perturbations of constant vector fields on a torus. As a side effect the result may be the shortest complete KAM proof for perturbations of integrable vector fields available so far.

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Jürgen Pöschel. 2009-09-06. KAM \`{a} la R. https://doi.org/10.1134/s1560354710520060

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