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arXiv · cond-mat/0410609

The thermal Casimir effect in lipid bilayer tubules

D. S. Dean·R. R. Horgan
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Abstract

We calculate the thermal Casimir effect for a dielectric tube of radius $R$ and thickness delta formed from a membrane in water. The method uses a field-theoretic approach in the grand canonical ensemble. The leading contribution to the Casimir free energy behaves as -k_BTL kappa_C/R giving rise to an attractive force which tends to contract the tube. We find that kappa_C ~ 0.3 for the case of typical lipid membrane t-tubules. We conclude that except in the case of a very soft membrane this force is insufficient to stabilize such tubes against the bending stress which tends to increase the radius.

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D. S. Dean, R. R. Horgan. 2004-10-25. The thermal Casimir effect in lipid bilayer tubules. https://doi.org/10.1103/physreve.71.041907

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