论文标题
用于振兴动力学模型系统中的拓扑力
Topological Forces in a Model System for Reptation Dynamics
论文作者
论文摘要
我们为拓扑约束聚合物的早期模型构建了一个微机械版本，这是一个类似点状的障碍物中的2D链，这使我们能够明确阐明除将链条限制在曲线管类似曲线的途径之外的拓扑作用。我们的模拟表明，轮廓长度\ textit {沿着管}的线性松弛会因拓扑力的存在而减慢，拓扑作用可以被视为静止中的其他有效拓扑'''。然而，这种观点无法预测在非线性启动微变学期间抵抗链条施加的曲线运动的强力。这些熵力本质上是非本质的，是由于方向和纵向动力学之间意外的耦合而引起的。
We construct a micromechanical version of an early model for topologically constrained polymers -- a 2D chain amongst point-like uncrossable obstacles -- which allows us to explicitly elucidate the role of topological forces beyond confining the chain to a curvilinear tube-like path. Our simulations reveal that linear relaxation of the contour length \textit{along the tube} is slowed down by the presence of topological forces that can be considered as additional effective topological ``friction'' in quiescence. However, this perspective fails in predicting the strong forces that resist the imposed curvilinear motion of the chain during nonlinear startup microrheology. These entropic forces are nonlocal in nature and result from an unexpected coupling between orientational and longitudinal dynamics.
