{ "id": "2104.13334", "version": "v1", "published": "2021-04-27T17:14:35.000Z", "updated": "2021-04-27T17:14:35.000Z", "title": "Derivation of the Onsager Principle from Large Deviation Theory", "authors": [ "Brian R. La Cour", "William C. Schieve" ], "comment": "25 pages, 3 figures", "journal": "Physica A 331, 109 (2004)", "doi": "10.1016/j.physa.2003.09.005", "categories": [ "cond-mat.stat-mech" ], "abstract": "The Onsager linear relations between macroscopic flows and thermodynamics forces are derived from the point of view of large deviation theory. For a given set of macroscopic variables, we consider the short-time evolution of near-equilibrium fluctuations, represented as the limit of finite-size conditional expectations. The resulting asymptotic conditional expectation is taken to represent the typical macrostate of the system and is used in place of the usual time-averaged macrostate of traditional approaches. By expanding in the short-time, near-equilibrium limit and equating the large deviation rate function with the thermodynamic entropy, a linear relation is obtained between the time rate of change of the macrostate and the conjugate initial macrostate. A Green-Kubo formula for the Onsager matrix is derived and shown to be positive semi-definite, while the Onsager reciprocity relations readily follow from time reversal invariance. Although the initial tendency of a macroscopic variable is to evolve towards equilibrium, we find that this evolution need not be monotonic. The example of an ideal Knundsen gas is considered as an illustration.", "revisions": [ { "version": "v1", "updated": "2021-04-27T17:14:35.000Z" } ], "analyses": { "keywords": [ "large deviation theory", "onsager principle", "large deviation rate function", "derivation", "onsager reciprocity relations" ], "tags": [ "journal article" ], "publication": { "publisher": "Elsevier" }, "note": { "typesetting": "TeX", "pages": 25, "language": "en", "license": "arXiv", "status": "editable" } } }