{ "id": "cond-mat/0501417", "version": "v1", "published": "2005-01-18T12:29:02.000Z", "updated": "2005-01-18T12:29:02.000Z", "title": "Nonextensive statistics in viscous fingering", "authors": [ "Patrick Grosfils", "Jean Pierre Boon" ], "comment": "8 pages including 3 figures; to appear in PHYSICA A", "doi": "10.1016/j.physa.2005.09.007", "categories": [ "cond-mat.stat-mech" ], "abstract": "Measurements in turbulent flows have revealed that the velocity field in nonequilibrium systems exhibits $q$-exponential or power law distributions in agreement with theoretical arguments based on nonextensive statistical mechanics. Here we consider Hele-Shaw flow as simulated by the Lattice Boltzmann method and find similar behavior from the analysis of velocity field measurements. For the transverse velocity, we obtain a spatial $q$-Gaussian profile and a power law velocity distribution over all measured decades. To explain these results, we suggest theoretical arguments based on Darcy's law combined with the non-linear advection-diffusion equation for the concentration field. Power law and $q$-exponential distributions are the signature of nonequilibrium systems with long-range interactions and/or long-time correlations, and therefore provide insight to the mechanism of the onset of fingering processes.", "revisions": [ { "version": "v1", "updated": "2005-01-18T12:29:02.000Z" } ], "analyses": { "keywords": [ "nonextensive statistics", "viscous fingering", "nonequilibrium systems", "power law velocity distribution", "theoretical arguments" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 8, "language": "en", "license": "arXiv", "status": "editable" } } }