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arXiv · 2507.02662

High order uniform in time schemes for weakly nonlinear Schr\"odinger equation and wave turbulence

Quentin Chauleur·Antoine Mouzard
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Abstract

We introduce two multiscale numerical schemes for the time integration of weakly nonlinear Schr\"odinger equations, built upon the discretization of Picard iterates of the solution. These high-order schemes are designed to achieve high precision with respect to the small nonlinearity parameter under particular CFL condition. By exploiting the scattering properties of these schemes thanks to a low-frequency projected linear flow, we also establish its uniform accuracy over long time horizons. Numerical simulations are provided to illustrate the theoretical results, and these schemes are further applied to investigate dynamics in the framework of wave turbulence.

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Quentin Chauleur, Antoine Mouzard. 2025-07-03. High order uniform in time schemes for weakly nonlinear Schr\"odinger equation and wave turbulence. https://arxiv.org/abs/2507.02662

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