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arXiv · 2206.03000

A toy model for viscous liquid dynamics

Filip Samuelsen·Lorenzo Costigliola·Thomas B. Schrøder
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Abstract

A simple model for viscous liquid dynamics is introduced. Consider the surface of the union of hyper-spheres centered at random positions inside a hypercube with periodic boundary conditions. It is argued and demonstrated by numerical simulations that at high dimensions geodetic flows on this surface is a good model for viscous liquid dynamics. It is shown that this simple model exhibits viscous dynamics for densities above the percolation threshold in $8$, $12$ and $16$ dimensions. Thus the slowing down of the dynamics, measured by the mean-squared displacement, extends to several orders of magnitude similarly to what is observed in other models for viscous dynamics. Furthermore, the shape of the mean-squared displacement is to a very good approximation the same as for the standard model in simulations of viscous liquids: the Kob-Andersen binary Lennard Jones mixture.

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Filip Samuelsen, Lorenzo Costigliola, Thomas B. Schrøder. 2022-06-07. A toy model for viscous liquid dynamics. https://arxiv.org/abs/2206.03000

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