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arXiv · 1903.05776

Directed aging, memory and Nature's greed

Nidhi Pashine·Daniel Hexner·Andrea J. Liu·Sidney R. Nagel
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Abstract

Disordered materials are often out of equilibrium and evolve very slowly. This allows a memory of the imposed strains or preparation conditions to be encoded in the material. Here we consider "directed aging", where the elastic properties of a material evolve in the direction defined by its aging history. The evolution to a lower-energy configuration is controlled by steepest decent and affects stressed regions differently from unstressed ones. This process can be considered to be a "greedy algorithm" of Nature. Our experiments and simulations illustrate directed aging in examples in which the material's elasticity evolves as a direct consequence of the imposed deformation; the material itself decides how to evolve in order to produce responses that were not present inherently in the material.

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Nidhi Pashine, Daniel Hexner, Andrea J. Liu, Sidney R. Nagel. 2019-03-14. Directed aging, memory and Nature's greed. https://doi.org/10.1126/sciadv.aax4215

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