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arXiv · 2309.03463

Lower dimensional invariant tori for multi-scale Hamiltonian systems

Weichao Qian·Shuguan Ji·Yong Li
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Abstract

The ``Fundamental Theorem" given by Arnold in [2] asserts the persistence of full dimensional invariant tori for 2-scale Hamiltonian systems. However, persistence in multi-scale systems is much more complicated and difficult. In this paper, we explore the persistence of lower dimensional invariant tori for multi-scale Hamiltonian systems, which play an important role in dynamics of resonant Hamiltonian systems. Moreover, using the corresponding results we give a quasi-periodic Poincar\'{e} Theorem for multi-scale Hamiltonian systems, i.e., at least $2^{m_0}$ families resonant tori survive small perturbations, where the integer $m_0$ is the multiplicity of resonance.

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Weichao Qian, Shuguan Ji, Yong Li. 2023-09-07. Lower dimensional invariant tori for multi-scale Hamiltonian systems. https://arxiv.org/abs/2309.03463

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