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arXiv · 2307.12652

Exact Global Control of Small Divisors in Rational Normal Form

Jianjun Liu·Duihui Xiang
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Abstract

Rational normal form is a powerful tool to deal with Hamiltonian partial differential equations without external parameters. In this paper, we build rational normal form with exact global control of small divisors. As an application to nonlinear Schr\"{o}dinger equations in Gevrey spaces, we prove sub-exponentially long time stability results for generic small initial data.

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Jianjun Liu, Duihui Xiang. 2023-07-24. Exact Global Control of Small Divisors in Rational Normal Form. https://arxiv.org/abs/2307.12652

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