Quasi-periodic solutions for quasi-linear generalized KdV equations

Filippo Giuliani

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arXiv · 1607.02583

Quasi-periodic solutions for quasi-linear generalized KdV equations

Filippo Giuliani

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Abstract

We prove the existence of Cantor families of small amplitude, linearly stable, quasi-periodic solutions of quasi-linear autonomous Hamiltonian generalized KdV equations. We consider the most general quasi-linear quadratic nonlinearity. The proof is based on an iterative Nash-Moser algorithm. To initialize this scheme, we need to perform a bifurcation analysis taking into account the strongly perturbative effects of the nonlinearity near the origin. In particular, we implement a weak version of the Birkhoff normal form method. The inversion of the linearized operators at each step of the iteration is achieved by pseudo-differential techniques, linear Birkhoff normal form algorithms and a linear KAM reducibility scheme.

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Filippo Giuliani. 2016-07-09. Quasi-periodic solutions for quasi-linear generalized KdV equations. https://arxiv.org/abs/1607.02583

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