title: Onsager symmetry from mesoscopic time reversibility and the hydrodynamic dispersion tensor for coarse-grained systems.
abstract: Onsager reciprocity relations derive from the fundamental time reversibility of the underlying microscopic equations of motion. This gives rise to a large set of symmetric cross-coupling phenomena. We here demonstrate that different reciprocity relations may arise from the notion of mesoscopic time reversibility, i.e., reversibility of intrinsically coarse-grained equations of motion. We use Brownian dynamics as an example of such a dynamical description and show how it gives rise to reciprocity in the hydrodynamic dispersion tensor as long as the background flow velocity is reversed as well.
authors.affiliation: Department of Physics, University of Oslo, P.O. Box 1043 Blindern, 0316 Oslo, Norway.
authors.forename: Eirik G
authors.initials: EG
authors.lastname: Flekkøy
authors.affiliation: Lawrence Berkeley National Laboratory, Earth Science Division, 1 Cyclotron Road, MS 90-1116, Berkeley, California 94720, USA.
authors.forename: Steven R
authors.initials: SR
authors.lastname: Pride
authors.affiliation: Institut de Physique du Globe de Strasbourg, University of Strasbourg/EOST, CNRS, 5 rue Descartes, F-67084 Strasbourg Cedex, France.
authors.forename: Renaud
authors.initials: R
authors.lastname: Toussaint