论文标题
泥土上的蜂群：二维不可压缩的羊群和淬火和退火障碍
Packed swarms on dirt: two-dimensional incompressible flocks with quenched and annealed disorder
论文作者
论文摘要
我们表明，不可压缩的极性活性流体即使在二维存在猝灭障碍的情况下，也可以表现出有序的，连贯的移动相。与这种活跃的流体不同（即仅是时间依赖性）疾病，其行为像平衡的铁磁体具有远距离相互作用，这种对淬灭疾病的鲁棒性是一种根本上非平衡现象。有序状态属于一个新的普遍性类别，我们使用三种不同的重新归一化组方案计算其缩放定律，它们彼此之间的缩放指数均在0.02之内，这表明我们的结果非常准确。我们的预测可以在随时可用的人工活动系统中进行定量测试，这意味着像细胞层这样的生物系统可以在不可避免的情况下在体内连贯地移动。
We show that incompressible polar active fluids can exhibit an ordered, coherently moving phase even in the presence of quenched disorder in two dimensions. Unlike such active fluids with annealed (i.e., time-dependent) disorder only, which behave like equilibrium ferromagnets with long-range interactions, this robustness against quenched disorder is a fundamentally non-equilibrium phenomenon. The ordered state belongs to a new universality class, whose scaling laws we calculate using three different renormalization group schemes, which all give scaling exponents within 0.02 of each other, indicating that our results are quite accurate. Our predictions can be quantitatively tested in readily available artificial active systems, and imply that biological systems such as cell layers can move coherently in vivo, where disorder is inevitable.
