Memory formation in dense persistent active matter

Elisabeth Agoritsas; Peter K. Morse

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arXiv · 2403.11701

Memory formation in dense persistent active matter

Elisabeth Agoritsas·Peter K. Morse

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Abstract

Protocol-dependent states in structural glasses can encode a disordered, yet retrievable memory. While training such materials is typically done via a global drive, such as external shear, in dense active matter the driving is instead local and spatio-temporally correlated. Here we focus on the impact of such spatial correlation on memory formation. We investigate the mechanical response of a dense amorphous packing of athermal particles, subject to an oscillatory quasistatic driving with a tunable spatial correlation, akin to the instantaneous driving pattern in active matter. We find that the capacity to encode memory can be rendered comparable upon a proper rescaling on the spatial correlation, whereas the efficiency in memory formation increases with motion cooperativity.

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cond-mat.soft cond-mat.dis-nn cond-mat.stat-mech

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Elisabeth Agoritsas, Peter K. Morse. 2024-03-18. Memory formation in dense persistent active matter. https://arxiv.org/abs/2403.11701

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