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arXiv · 1102.4508

Effective Temperature of Red Blood Cell Membrane Fluctuations

Eyal Ben-Isaac·YongKeun Park·Gabriel Popescu·Frank L. H. Brown·Nir S. Gov·Yair Shokef
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Abstract

Biologically driven non-equilibrium fluctuations are often characterized by their non-Gaussianity or by an "effective temperature", which is frequency dependent and higher than the ambient temperature. We address these two measures theoretically by examining a randomly kicked "particle", with a variable number of kicking "motors", and show how these two indicators of non-equilibrium behavior can contradict. Our results are compared with new experiments on shape fluctuations of red-blood cell membranes, and demonstrate how the physical nature of the motors in this system can be revealed using these global measures of non-equilibrium.

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Eyal Ben-Isaac, YongKeun Park, Gabriel Popescu, Frank L. H. Brown, Nir S. Gov, Yair Shokef. 2011-05-04. Effective Temperature of Red Blood Cell Membrane Fluctuations. https://doi.org/10.1103/physrevlett.106.238103

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