{ "id": "0705.4366", "version": "v2", "published": "2007-05-30T11:23:14.000Z", "updated": "2008-11-20T17:05:06.000Z", "title": "Critical mass of bacterial populations in a generalized Keller-Segel model. Analogy with the Chandrasekhar limiting mass of white dwarf stars", "authors": [ "Pierre-Henri Chavanis", "Clement Sire" ], "journal": "Physica A, 387, 1999 (2008)", "doi": "10.1016/j.physa.2007.10.075", "categories": [ "cond-mat.stat-mech" ], "abstract": "We point out a remarkable analogy between the limiting mass of white dwarf stars (Chandrasekhar's limit) and the critical mass of bacterial populations in a generalized Keller-Segel model of chemotaxis [Chavanis & Sire, PRE, 69, 016116 (2004)]. This model is based on generalized stochastic processes leading to the Tsallis statistics. The equilibrium states correspond to polytropic configurations similar to gaseous polytropes in astrophysics. For the critical index n_3=d/(d-2) (where d is the dimension of space), the theory of polytropes leads to a unique value of the mass M_c that we interpret as a limiting mass. In d=3, we find M_c=202.8956... and in d=2, we recover the well-known result M_c=8 pi (in suitable units). For MM_c, the system collapses and forms a Dirac peak containing a mass M_c surrounded by a halo. This paper exposes the model and shows, by simple considerations, the origin of the critical mass. A detailed description of the critical dynamics of the generalized Keller-Segel model will be given in a forthcoming paper.", "revisions": [ { "version": "v2", "updated": "2008-11-20T17:05:06.000Z" } ], "analyses": { "keywords": [ "generalized keller-segel model", "white dwarf stars", "critical mass", "chandrasekhar limiting mass", "bacterial populations" ], "tags": [ "journal article" ], "publication": { "journal": "Physica A Statistical Mechanics and its Applications", "year": 2008, "month": "Mar", "volume": 387, "number": "8-9", "pages": 1999 }, "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2008PhyA..387.1999C" } } }