Screening by symmetry of long-range hydrodynamic interactions of polymers confined in sheets

Tsvi Tlusty

doi:10.1021/ma060251d

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arXiv · 1008.0400

Screening by symmetry of long-range hydrodynamic interactions of polymers confined in sheets

Tsvi Tlusty

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Abstract

Hydrodynamic forces may significantly affect the motion of polymers. In sheet-like cavities, such as the cell's cytoplasm and microfluidic channels, the hydrodynamic forces are long-range. It is therefore expected that that hydrodynamic interactions will dominate the motion of polymers in sheets and will be manifested by Zimm-like scaling. Quite the opposite, we note here that although the hydrodynamic forces are long-range their overall effect on the motion of polymers vanishes due to the symmetry of the two-dimensional flow. As a result, the predicted scaling of experimental observables such as the diffusion coefficient or the rotational diffusion time is Rouse-like, in accord with recent experiments. The effective screening validates the use of the non-interacting blobs picture for polymers confined in a sheet.

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Tsvi Tlusty. 2010-08-02. Screening by symmetry of long-range hydrodynamic interactions of polymers confined in sheets. https://doi.org/10.1021/ma060251d

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