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A Renormalization Proof of the KAM Theorem for Non-Analytic Perturbations

Emiliano De Simone
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Abstract

We shall use a Renormalization Group (RG) scheme in order to prove the classical KAM result in the case of a non-analytic perturbation (the latter will be assumed to have continuous derivatives up to a sufficiently large order). We shall proceed by solving a sequence of problems in which the perturbations are analytic approximations of the original one. We shall finally show that the sequence of the approximate solutions will converge to a differentiable solution of the original problem.

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Emiliano De Simone. 2006-11-15. A Renormalization Proof of the KAM Theorem for Non-Analytic Perturbations. https://doi.org/10.1142/s0129055x07003085

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