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arXiv · 2409.01507

Stability of Rayleigh-Jeans equilibria in the kinetic FPU equation

Pierre Germain·Joonhyun La·Angeliki Menegaki
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Abstract

We study the nonlinear dynamics of the kinetic wave equation associated to the FPU problem and prove stability of the non-singular Rayleigh-Jeans equilibria. The lack of a spectral gap for the linearized problem leads to polynomial decay, which we are able to leverage to obtain nonlinear stability.

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Pierre Germain, Joonhyun La, Angeliki Menegaki. 2024-09-03. Stability of Rayleigh-Jeans equilibria in the kinetic FPU equation. https://arxiv.org/abs/2409.01507

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