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arXiv · cond-mat/9909367

Conserved Linking in Single- and Double-Stranded Polymers

Joseph S. Plewa·Thomas A. Witten
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Abstract

We demonstrate a variant of the Bond Fluctuation lattice Monte Carlo model in which moves through cis conformations are forbidden. Ring polymers in this model have a conserved quantity that amounts to a topological linking number. Increased linking number reduces the radius of gyration mildly. A linking number of order 0.2 per bond leads to an eight-percent reduction of the radius for 128-bond chains. This percentage appears to rise with increasing chain length, contrary to expectation. For ring chains evolving without the conservation of linking number, we demonstrate a substantial anti-correlation between the twist and writhe variables whose sum yields the linking number. We raise the possibility that our observed anti-correlations may have counterparts in the most important practical polymer that conserves linking number, DNA.

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Joseph S. Plewa, Thomas A. Witten. 2000-02-09. Conserved Linking in Single- and Double-Stranded Polymers. https://doi.org/10.1063/1.481639

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