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arXiv · 2610.19935

Stability of inverse cascade in NLS Wave turbulence

Guillaume Costa·Sergey Nazarenko·Giorgio Krstulovic
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Abstract

We study the stability of the inverse cascade in the 3D Nonlinear Schrodinger Wave Kinetic Equation (WKE) in the presence and absence of a condensate. Using theoretical arguments supported by numerical simulation, we show that, the Kolmogorov-Zakharov solution is stable with respect to small isotropic perturbations in the absence of a condensate. Conversely, introducing a condensate component leads to a growth of the condensate occupation and ultimately destabilizes the inverse cascade. The system then evolves towards a new steady-state whose properties depend on the condensate dissipation rate.

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Guillaume Costa, Sergey Nazarenko, Giorgio Krstulovic. 2026-10-14. Stability of inverse cascade in NLS Wave turbulence. https://arxiv.org/abs/2610.19935

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