Mesoscopic theory for fluctuating active nematics
Mesoscopic theory for fluctuating active nematics
复制标题
DOI：
10.1088/1367-2630/15/8/085032
复制
发表时间：
2013-08-28
影响因子：
3.3
通讯作者：
Ramaswamy, Sriram
中科院分区：
文献类型：
--
作者：
Bertin, Eric;Chate, Hugues;Ramaswamy, Sriram
活跃向列学一词指的是非极细长粒子花费能量沿其轴线随机运动，并在存在噪声的情况下通过非弹性碰撞相互作用的系统。从一个简单的Vicsek式的主动向列学模型出发，我们结合了动力学理论和伊藤微积分的方法，得到了一个带有有效乘性噪声项的介观理论。由此得到的随机偏微分方程式被证明恢复了Ramaswamy等人(2003 Europhys)中所争论的关键项。让我们来吧。62 196)是数的异常起伏和长程相关的起源。它们的决定论部分被解析地研究，并且被证明在向列序开始时引起长波不稳定性(见ShiX和Ma Y2010arxiv：1011.5408)。给出了相应的闭合形式的非线性密度分离带解。
The term active nematics designates systems in which apolar elongated particles spend energy to move randomly along their axis and interact by inelastic collisions in the presence of noise. Starting from a simple Vicsek-style model for active nematics, we derive a mesoscopic theory, complete with effective multiplicative noise terms, using a combination of kinetic theory and Ito calculus approaches. The stochastic partial differential equations thus obtained are shown to recover the key terms argued in Ramaswamy et al (2003 Europhys. Lett. 62 196) to be at the origin of anomalous number fluctuations and long-range correlations. Their deterministic part is studied analytically, and is shown to give rise to the long-wavelength instability at onset of nematic order (see Shi X and Ma Y 2010 arXiv:1011.5408). The corresponding nonlinear density-segregated band solution is given in a closed form.