2010/05/07 by Michael Schindler · 19 citations
Earth and Planetary Sciences · Materials Science · Mathematics · Physics and Astronomy · #Cauchy stress tensor #Classical mechanics #Computer science #Correlation function (quantum field theory) #Function (biology) #Geometry #High-pressure geophysics and materials #Isotropy #Material Dynamics and Properties #Mathematics #Mechanics #Molecular dynamics #Optics #Physics #Quantum mechanics #Relaxation (psychology) #Space (punctuation) #Statistical physics #Stress (linguistics) #Tensor (intrinsic definition) #Theoretical and Computational Physics #Viscous stress tensor #cond-mat.soft #physics.chem-ph #physics.flu-dyn
paper · pdf · doi:10.1016/j.chemphys.2010.05.008
published in Chemical Physics 375(2-3), 327-336 (Elsevier BV) · 12 pages, 10 figures. To be published in the special issue "Stochastic Processes in Physics and Chemistry" of Chemical Physics, on occasion of Peter Hanggi's 60th birthday
arxiv created 2010/05/07 · openalex publication_date 2010/05/20 · arxiv updated 2012/01/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The correlations of the fluctuating stress tensor are calculated in an equilibrium molecular-dynamics simulation of a Lennard--Jones liquid. We define a coarse-grained local stress tensor which can be calculated numerically and which allows for the first time to determine the stress correlation function both in time and in space. Our findings corroborate the assumptions made in fluctuating hydrodynamics as long as the liquid is isotropic, that is in bulk. In the vicinity of a rigid plate, however, the isotropy is restricted, and major modifications must be done with respect to the usual theory. Among these are the appearance of five different viscosities instead of two and a non-trivial dependence of the distance from the wall. We determine these viscosities from the simulation data and find that their values are very different from the bulk values. We further find much longer relaxation times of the stress correlations than in bulk.