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arXiv · 1909.04099

A KAM Theorem for finitely differentiable Hamiltonian systems

Comlan Edmond Koudjinan
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Abstract

Given $l>2\nu>2d\geq 4$, we prove the persistence of a Cantor--family of KAM tori of measure $O(\varepsilon^{1/2-\nu/l})$ for any non--degenerate nearly integrable Hamiltonian system of class $C^l(\mathscr D\times\mathbb{T}^d)$, where $\mathscr D\subset \mathbb{R}^d$ is a bounded domain, provided that the size $\varepsilon$ of the perturbation is sufficiently small. This extends a result by D. Salamon in \cite{salamon2004kolmogorov} according to which we do have the persistence of a single KAM torus in the same framework. Moreover, it is well--known that, for the persistence of a single torus, the regularity assumption can not be improved.

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Comlan Edmond Koudjinan. 2019-09-09. A KAM Theorem for finitely differentiable Hamiltonian systems. https://doi.org/10.1016/j.jde.2020.03.044

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