{ "id": "1102.4062", "version": "v1", "published": "2011-02-20T10:47:19.000Z", "updated": "2011-02-20T10:47:19.000Z", "title": "Dimension of attractors and invariant sets in reaction diffusion equations", "authors": [ "Martino Prizzi" ], "comment": "20 pages", "categories": [ "math.AP", "math.DS" ], "abstract": "Under fairly general assumptions, we prove that every compact invariant set $\\mathcal I$ of the semiflow generated by the semilinear reaction diffusion equation u_t+\\beta(x)u-\\Delta u&=f(x,u),&&(t,x)\\in[0,+\\infty[\\times\\Omega, u&=0,&&(t,x)\\in[0,+\\infty[\\times\\partial\\Omega} {equation*} in $H^1_0(\\Omega)$ has finite Hausdorff dimension. Here $\\Omega$ is an arbitrary, possibly unbounded, domain in $\\R^3$ and $f(x,u)$ is a nonlinearity of subcritical growth. The nonlinearity $f(x,u)$ needs not to satisfy any dissipativeness assumption and the invariant subset $\\mathcal I$ needs not to be an an attractor. If $\\Omega$ is regular, $f(x,u)$ is dissipative and $\\mathcal I$ is the global attractor, we give an explicit bound on the Hausdorff dimension of $\\mathcal I$ in terms of the structure parameter of the equation.", "revisions": [ { "version": "v1", "updated": "2011-02-20T10:47:19.000Z" } ], "analyses": { "subjects": [ "35B41", "35K57" ], "keywords": [ "semilinear reaction diffusion equation", "finite hausdorff dimension", "compact invariant set", "global attractor", "structure parameter" ], "note": { "typesetting": "TeX", "pages": 20, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2011arXiv1102.4062P" } } }