The Glassy Wormlike Chain

TL;DR

The paper introduces the glassy wormlike chain model, which captures the complex dynamics of biopolymer networks in rough energy landscapes, aligning well with experimental observations of cellular structures.

Contribution

It proposes a novel model that modifies the wormlike chain by stretching its relaxation spectrum, providing a better understanding of soft glassy rheology in biological systems.

Findings

Model accurately predicts dynamic structure factor and microrheological susceptibility.

Results align with experimental data from cytoskeletal networks and live cells.

Suggests microscopic origins and implications for nonlinear rheology.

Abstract

We introduce a new model for the dynamics of a wormlike chain in an environment that gives rise to a rough free energy landscape, which we baptise the glassy wormlike chain. It is obtained from the common wormlike chain by an exponential stretching of the relaxation spectrum of its long-wavelength eigenmodes, controlled by a single stretching parameter. Predictions for pertinent observables such as the dynamic structure factor and the microrheological susceptibility exhibit the characteristics of soft glassy rheology and compare favourably with experimental data for reconstituted cytoskeletal networks and live cells. We speculate about the possible microscopic origin of the stretching, implications for the nonlinear rheology, and the potential physiological significance of our results.