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arXiv · 2510.11825

Memories of amplitude and direction coexist and compete in non-Brownian suspensions

Surendra Padamata·Nathan C. Keim
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Abstract

Steadily shearing a non-Brownian suspension forms a memory of direction, while shearing back and forth forms a memory of amplitude. Each memory is evident in the systems response to further shear, exemplifying its strong history-dependence. By combining the steady and oscillatory experiments, we show these memories are distinct but intersecting aspects of the same non-equilibrium physics: they can coexist, yet a specific amplitude suppresses directional memory and makes the system symmetric. Combined with prior results from disordered solids, our work presents a simple motif for limited memory capacity in non-equilibrium matter.

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Surendra Padamata, Nathan C. Keim. 2025-10-13. Memories of amplitude and direction coexist and compete in non-Brownian suspensions. https://doi.org/10.1103/ckl2-lcpl

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