Random bursts determine dynamics of active filaments

作者：Christoph Andreas Weber, Ryo Suzuki, Volker Schaller, Igor S. Aranson, Andreas R. Bausch, Erwin Frey · 发表于：Proceedings of the National Academy of Sciences · 年份：2015 · DOI：10.1073/pnas.1421322112 · 被引用次数：60 · 研究领域：Micro and Nano Robotics、Advanced Thermodynamics and Statistical Mechanics、Molecular Communication and Nanonetworks

Constituents of living or synthetic active matter have access to a local energy supply that serves to keep the system out of thermal equilibrium. The statistical properties of such fluctuating active systems differ from those of their equilibrium counterparts. Using the actin filament gliding assay as a model, we studied how nonthermal distributions emerge in active matter. We found that the basic mechanism involves the interplay between local and random injection of energy, acting as an analog of a thermal heat bath, and nonequilibrium energy dissipation processes associated with sudden jump-like changes in the system's dynamic variables. We show here how such a mechanism leads to a nonthermal distribution of filament curvatures with a non-Gaussian shape. The experimental curvature statistics and filament relaxation dynamics are reproduced quantitatively by stochastic computer simulations and a simple kinetic model.