Diffusion cascade in a model of interacting random walkers

Abhishek Raj; Paolo Glorioso; Sarang Gopalakrishnan; Vadim Oganesyan

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arXiv · 2412.05222

Diffusion cascade in a model of interacting random walkers

Abhishek Raj·Paolo Glorioso·Sarang Gopalakrishnan·Vadim Oganesyan

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Abstract

We consider the relaxation of finite-wavevector density waves in a facilitated classical lattice gas. Linear hydrodynamics predicts that such perturbations should relax exponentially, but nonlinear effects were predicted to cause subexponential relaxation via nonperturbative long-time tails. We present a detailed numerical study of this effect. While our results clearly indicate the importance of nonlinear effects, we find that the wavevector-dependence of the late-time relaxation is clearly inconsistent with theoretical predictions. We discuss manifestations of hydrodynamic nonlinearities in mesoscopic samples and at short times.

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Abhishek Raj, Paolo Glorioso, Sarang Gopalakrishnan, Vadim Oganesyan. 2024-12-06. Diffusion cascade in a model of interacting random walkers. https://arxiv.org/abs/2412.05222

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