论文标题
活性流体中的时间逆转对称性断裂和奇特的粘度：绿色kubo和NEMD结果
Time reversal symmetry breaking and odd viscosity in active fluids: Green-Kubo and NEMD results
论文作者
论文摘要
由于时间逆转对称性破坏，通过非保守力在微观上驱动的活性流体会表现出新型的运输现象。最近，爱泼斯坦（Epstein）和曼达达普（Mandadapu）[Arxiv：1907.10041]获得了绿色的关系，以制作整个管理各向同性性手性活性流体的粘性系数，包括所谓的奇特粘度，包括Onsager的回归假设，以使现有非平衡状态的衰减为衰减，以使其衰减。在这种交流中，我们使用由主动扭矩的哑铃组成的规范模型系统的分子动力学模拟测试了这些绿色 - 库博关系。我们发现，绿色kubo关系的奇数和剪切粘度值与通过非平衡分子动力学（NEMD）流动模拟独立测量的值非常吻合。这提供了对绿色 - 库博关系的测试，并为Onsager回归假设的应用提供了支持与活动物质系统粘性行为有关的支持。
Active fluids, which are driven at the microscale by non-conservative forces, are known to exhibit novel transport phenomena due to the breaking of time reversal symmetry. Recently, Epstein and Mandadapu [arXiv:1907.10041] obtained Green-Kubo relations for the full set of viscous coefficients governing isotropic chiral active fluids, including the so-called odd viscosity, invoking Onsager's regression hypothesis for the decay of fluctuations in active non-equilibrium steady states. In this Communication, we test these Green-Kubo relations using molecular dynamics simulations of a canonical model system consisting of actively torqued dumbbells. We find the resulting odd and shear viscosity values from the Green-Kubo relations to be in good agreement with values measured independently through non-equilibrium molecular dynamics (NEMD) flow simulations. This provides a test of the Green-Kubo relations, and lends support to the application of the Onsager regression hypothesis in relation to viscous behaviors of active matter systems.
