论文标题
拥挤增强的扩散：高度纠缠的自propeld僵硬细丝的确切理论
Crowding-Enhanced Diffusion: An Exact Theory for Highly Entangled Self-Propelled Stiff Filaments
论文作者
论文摘要
我们通过事件驱动的布朗动力学模拟和分析理论研究了一个强烈相互作用的拥挤的自行僵硬细丝系统，以阐明拥挤和自我推测的复杂相互作用。我们发现，在将灯丝数量密度增加一个数量级时，有效扩散率显着提高。通过扩展Doi和Edwards率先使用的限制管的概念，可以合理地将这种违反直觉的“拥挤的人”行为合理化，以实现高度纠结的拥挤，被动地对活跃系统。我们预测了有效扩散率的缩放理论，它是péclet数量和灯丝数量密度的函数。随后，我们表明，带有运动参数的单个自旋细丝的精确表达式，因为输入可以预测整个长度和时间尺度范围内的非平凡时空动力学。特别是，我们的理论捕获了短期的扩散，在中间时间进行了定向游泳运动，并长期捕获了完整的定向放松的过渡。
We study a strongly interacting crowded system of self-propelled stiff filaments by event-driven Brownian dynamics simulations and an analytical theory to elucidate the intricate interplay of crowding and self-propulsion. We find a remarkable increase of the effective diffusivity upon increasing the filament number density by more than one order of magnitude. This counter-intuitive 'crowded is faster' behavior can be rationalized by extending the concept of a confining tube pioneered by Doi and Edwards for highly entangled crowded, passive to active systems. We predict a scaling theory for the effective diffusivity as a function of the Péclet number and the filament number density. Subsequently, we show that an exact expression derived for a single self-propelled filament with motility parameters as input can predict the non-trivial spatiotemporal dynamics over the entire range of length and time scales. In particular, our theory captures short-time diffusion, directed swimming motion at intermediate times, and the transition to complete orientational relaxation at long times.
