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arXiv · 2211.13076

Birkhoff normal form in low regularity for the nonlinear quantum harmonic oscillator

Charbella Abou Khalil
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Abstract

Given small initial solutions of the nonlinear quantum harmonic oscillator on $\mathbb{R}$, we are interested in their long time behavior in the energy space which is an adapted Sobolev space. We perturbate the linear part by $V$ taken as multiplicative potentials, in a way that the linear frequencies satisfy a non-resonance condition. More precisely, we prove that for almost all potentials $V$, the low modes of the solution are almost preserved for very long times.

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Charbella Abou Khalil. 2022-11-23. Birkhoff normal form in low regularity for the nonlinear quantum harmonic oscillator. https://arxiv.org/abs/2211.13076

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