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arXiv · 1803.06580

Aging is a log-Poisson Process, not a Renewal Process

Stefan Boettcher·Dominic M. Robe·Paolo Sibani
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Abstract

Aging is a ubiquitous relaxation dynamic in disordered materials. It ensues after a rapid quench from an equilibrium "fluid" state into a non-equilibrium, history-dependent jammed state. We propose a physically motivated description that contrasts sharply with a continuous-time random walk (CTRW) with broadly distributed trapping times commonly used to fit aging data. A renewal process like CTRW proves irreconcilable with the log-Poisson statistic exhibited, for example, by jammed colloids as well as by disordered magnets. A log-Poisson process is characteristic of the intermittent and decelerating dynamics of jammed matter usually activated by record-breaking fluctuations ("quakes"). We show that such a record dynamics (RD) provides a universal model for aging, physically grounded in generic features of free-energy landscapes of disordered systems.

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Stefan Boettcher, Dominic M. Robe, Paolo Sibani. 2018-08-22. Aging is a log-Poisson Process, not a Renewal Process. https://doi.org/10.1103/physreve.98.020602

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