Memory formation in jammed hard spheres

Patrick Charbonneau; Peter Morse

doi:10.1103/physrevlett.126.088001

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arXiv · 2009.00492

Memory formation in jammed hard spheres

Patrick Charbonneau·Peter Morse

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Abstract

Liquids equilibrated below an onset density share similar inherent states, while above that density their inherent states markedly differ. Although this phenomenon was first reported in simulations over 20 years ago, the physical origin of this memory remains controversial. Its absence from mean-field descriptions, in particular, has long cast doubt on its thermodynamic relevance. Motivated by a recent theoretical proposal, we reassess the onset phenomenology in simulations using a fast hard sphere jamming algorithm and find it both thermodynamically and dimensionally robust. Remarkably, we also uncover a second type of memory associated with a Gardner-like change in behavior along the jamming algorithm.

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Patrick Charbonneau, Peter Morse. 2020-09-01. Memory formation in jammed hard spheres. https://doi.org/10.1103/physrevlett.126.088001

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