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Entropic Tightening of Vibrated Chains

M. B. Hastings·Z. A. Daya·E. Ben-Naim·R. E. Ecke
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Abstract

We investigate experimentally the distribution of configurations of a ring with an elementary topological constraint, a ``figure-8'' twist. Using vibrated granular chains, which permit controlled preparation and direct observation of such a constraint, we show that configurations where one of the loops is tight and the second is large are strongly preferred. This agrees with recent predictions for equilibrium properties of topologically-constrained polymers. However, the dynamics of the tightening process weakly violate detailed balance, a signature of the nonequilibrium nature of this system.

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M. B. Hastings, Z. A. Daya, E. Ben-Naim, R. E. Ecke. 2001-10-30. Entropic Tightening of Vibrated Chains. https://doi.org/10.1103/physreve.66.025102

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