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arXiv · 2411.08030

Integrable fishnet circuits and Brownian solitons

Žiga Krajnik·Enej Ilievski·Tomaž Prosen·Benjamin J. A. Héry·Vincent Pasquier
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Abstract

We introduce classical many-body dynamics on a one-dimensional lattice comprising local two-body maps arranged on discrete space-time mesh that serve as discretizations of Hamiltonian dynamics with arbitrarily time-varying coupling constants. Time evolution is generated by passing an auxiliary degree of freedom along the lattice, resulting in a `fishnet' circuit structure. We construct integrable circuits consisting of Yang-Baxter maps and demonstrate their general properties, using the Toda and anisotropic Landau-Lifschitz models as examples. Upon stochastically rescaling time, the dynamics is dominated by fluctuations and we observe solitons undergoing Brownian motion.

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Žiga Krajnik, Enej Ilievski, Tomaž Prosen, Benjamin J. A. Héry, Vincent Pasquier. 2025-05-06. Integrable fishnet circuits and Brownian solitons. https://doi.org/10.21468/scipostphys.19.1.027

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