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Size distribution of ring polymers.

ABSTRACT: We present an exact solution for the distribution of sample averaged monomer to monomer distance of ring polymers. For non-interacting and local-interaction models these distributions correspond to the distribution of the area under the reflected Bessel bridge and the Bessel excursion respectively, and are shown to be identical in dimension d???2, albeit with pronounced finite size effects at the critical dimension, d?=?2. A symmetry of the problem reveals that dimension d and 4?-?d are equivalent, thus the celebrated Airy distribution describing the areal distribution of the d?=?1 Brownian excursion describes also a polymer in three dimensions. For a self-avoiding polymer in dimension d we find numerically that the fluctuations of the scaled averaged distance are nearly identical in dimension d?=?2, 3 and are well described to a first approximation by the non-interacting excursion model in dimension 5.

SUBMITTER: Medalion S

PROVIDER: S-EPMC4908590 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Size distribution of ring polymers.

Medalion Shlomi S Aghion Erez E Meirovitch Hagai H Barkai Eli E Kessler David A DA

Scientific reports 20160615

We present an exact solution for the distribution of sample averaged monomer to monomer distance of ring polymers. For non-interacting and local-interaction models these distributions correspond to the distribution of the area under the reflected Bessel bridge and the Bessel excursion respectively, and are shown to be identical in dimension d ≥ 2, albeit with pronounced finite size effects at the critical dimension, d = 2. A symmetry of the problem reveals that dimension d and 4 - d are equivale ...[more]

PMID: 27302596

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