论文标题
在空间异质环境中的拓扑羊群模型
Topological flocking models in spatially heterogeneous environments
论文作者
论文摘要
具有度量和拓扑相互作用的羊群模型应该表现出不同的特征，例如存在和不存在移动的极性带。另一方面，已经证明淬灭障碍（空间异质性）会极大地影响具有度量相互作用的活动系统的大规模特性，而淬灭症对具有无度相互作用的活动系统的影响一直保持不变。在这里，我们表明，拓扑羊群模型在均质介质中恢复了公制的几个特征，当放置在异质环境中时。特别是，我们发现即使存在空间异质性，秩序也长期存在，并且异质环境诱导有效的密度 - 密度耦合促进行进带的出现，这在广泛的参数空间中观察到。我们认为，这种耦合是由于拓扑相互作用网络的波动引起的重新布线而引起的，这通过空间异质性的存在强烈增强。
Flocking models with metric and topological interactions are supposed to exhibit distinct features, as for instance the presence and absence of moving polar bands. On the other hand, quenched disorder (spatial heterogeneities) has been shown to dramatically affect large-scale properties of active systems with metric interactions, while the impact of quenched disorder on active systems with metric-free interactions has remained, until now, unexplored. Here, we show that topological flocking models recover several features of metric ones in homogeneous media, when placed in a heterogeneous environment. In particular, we find that order is long-ranged even in the presence of spatial heterogeneities, and that the heterogeneous environment induces an effective density-order coupling facilitating emergence of traveling bands, which are observed in wide regions of parameter space. We argue that such a coupling results from a fluctuation-induced rewiring of the topological interaction network, strongly enhanced by the presence of spatial heterogeneities.
