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arXiv · 2008.00970

Fatigue and failure of a polymer chain under tension

Harish Charan·Alex Hansen·H. G. E. Hentschel·Itamar Procaccia
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Abstract

The rupture of a polymer chain maintained at temperature $T$ under fixed tension is prototypical to a wide array of systems failing under constant external strain and random perturbations. Past research focused on analytic and numerical studies of the mean rate of collapse of such a chain. Surprisingly, an analytic calculation of the probability distribution function (PDF) of collapse rates appears to be lacking. Since rare events of rapid collapse can be important and even catastrophic, we present here a theory of this distribution, with a stress on its tail of fast rates. We show that the tail of the PDF is a power law with a {\em universal} exponent that is theoretically determined. Extensive numerics validate the offered theory. Lessons pertaining to other problems of the same type are drawn.

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Harish Charan, Alex Hansen, H. G. E. Hentschel, Itamar Procaccia. 2020-07-30. Fatigue and failure of a polymer chain under tension. https://doi.org/10.1103/physrevlett.126.085501

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