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arXiv · 2601.04788

Ensemble of Fixed Points in Multi-branch Shell Models of Turbulent Cascades

Flavio Tuteri·Sergio Chibbaro·Alexandros Alexakis
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Abstract

Stationary solutions of a shell model of turbulence defined on a dyadic tree topology are studied. Each node's amplitude is expressed as the product of amplitude multipliers associated with its ancestors, providing a recursive representation of the cascade process. A geometrical rule governs the tree growth, and we prove the existence of a continuum of fixed points, including the Kolmogorov solution, that sustain a strictly forward energy cascade. Sampling along randomly chosen branches defines a homogeneous Markov chain, enabling a stochastic characterization of extended self-similarity and intermittency through the spectral properties of the associated Feynman-Kac operators. Numerical simulations confirm the theoretical predictions, showing that multi-branch shell models offer a minimal yet physically rich framework for exploring the complexity of nonlinear energy transfer across scales.

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Flavio Tuteri, Sergio Chibbaro, Alexandros Alexakis. 2026-01-08. Ensemble of Fixed Points in Multi-branch Shell Models of Turbulent Cascades. https://arxiv.org/abs/2601.04788

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