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arXiv · 0904.0206

Critical scaling and aging in cooling systems near the jamming transition

D. A. Head
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Abstract

We conduct athermal simulations of freely-cooling, viscous soft spheres around the jamming transition density ϕ_{J}, and find evidence for a growing length ξ(t) that governs relaxation to mechanical equilibrium. ξ(t) is manifest in both the velocity correlation function, and the spatial correlations in a scalar measure of local force balance which we define. Data for different densities ϕcan be collapsed onto two master curves by scaling ξ(t) and t by powers of |ϕ-ϕ_{J}|, indicative of critical scaling. Furthermore, particle transport for ϕ>ϕ_{J} exhibits aging and superdiffusion similar to a range of soft matter experiments, suggesting a common origin. Finally, we explain how ξ(t) at late times maps onto known behavior away from ϕ_{J}.

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D. A. Head. 2009-04-01. Critical scaling and aging in cooling systems near the jamming transition. https://doi.org/10.1103/physrevlett.102.138001

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