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Updated: May 17, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Irreversible Thermalization vs Reversible Dynamics Mediated by Anomalous Correlators: Wave Turbulence Theory and
T Torres1, J Garnier2, L Zanaglia3
1Laboratoire Interdisciplinaire Carnot de Bourgogne, CNRS, Université Bourgogne Europe, ICB UMR 6303, 21000 Dijon, France.
None:
We theoretically and experimentally investigate spontaneous self-organization in a conservative (Hamiltonian) turbulent wave system, operating far from thermodynamic equilibrium. Our system is governed by two coherently coupled nonlinear Schrödinger equations, describing the polarization evolution of light in a dispersive nonlinear optical fiber. The analysis reveals the emergence of two fundamentally distinct turbulent regimes. In a first regime, the waves undergo a slow, irreversible thermalization process, which is accurately described by the wave turbulence kinetic equation and the associated H theorem of entropy growth. In stark contrast with this expected irreversible process, we identify a second different regime, where strong phase correlations spontaneously emerge, giving rise to a fast reversible oscillatory dynamics of the normal correlator and anomalous phase correlator. Experimental observations confirm the occurrence of both irreversible thermalization and reversible dynamics mediated by the anomalous correlated fluctuations.
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