论文标题
乘法噪声和保守密度的扩散
Multiplicative noise and the diffusion of conserved densities
论文作者
论文摘要
随机流体动力学控制了流体动力相关函数的长时间尾巴，以及相图中临界点附近弛豫现象的临界减速。在这项工作中，我们研究了繁殖噪声在随机流体动力学中的作用。乘法噪声来自转运系数的依赖性，例如电荷和动量的扩散常数，对流动动力学变量的波动。我们研究了长时间的尾巴和放松，并在保守密度（B）的扩散中，以及与横向动量密度耦合的保守密度（模型H）。仔细注意波动的关系。我们观察到，乘法噪声与B中的非线性相互作用相同，但对于标量密度的松弛和压力张量相关功能的尾巴是模型H中的较高级校正。
Stochastic fluid dynamics governs the long time tails of hydrodynamic correlation functions, and the critical slowing down of relaxation phenomena in the vicinity of a critical point in the phase diagram. In this work we study the role of multiplicative noise in stochastic fluid dynamics. Multiplicative noise arises from the dependence of transport coefficients, such as the diffusion constants for charge and momentum, on fluctuating hydrodynamic variables. We study long time tails and relaxation in the diffusion of a conserved density (model B), and a conserved density coupled to the transverse momentum density (model H). Careful attention is paid to fluctuation-dissipation relations. We observe that multiplicative noise contributes at the same order as non-linear interactions in model B, but is a higher order correction to the relaxation of a scalar density and the tail of the stress tensor correlation function in model H.
