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arXiv · cond-mat/0702160

Metastable tight knots in a worm-like polymer

Alexander Y. Grosberg·Yitzhak Rabin
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Abstract

Based on an estimate of the knot entropy of a worm-like chain we predict that the interplay of bending energy and confinement entropy will result in a compact metastable configuration of the knot that will diffuse, without spreading, along the contour of the semi-flexible polymer until it reaches one of the chain ends. Our estimate of the size of the knot as a function of its topological invariant (ideal aspect ratio) agrees with recent experimental results of knotted dsDNA. Further experimental tests of our ideas are proposed.

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Alexander Y. Grosberg, Yitzhak Rabin. 2007-02-07. Metastable tight knots in a worm-like polymer. https://doi.org/10.1103/physrevlett.99.217801

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