{ "id": "1401.0351", "version": "v1", "published": "2014-01-02T01:03:16.000Z", "updated": "2014-01-02T01:03:16.000Z", "title": "On Second Order Elliptic and Parabolic Equations of Mixed Type", "authors": [ "Gong Chen", "Mikhail Safonov" ], "comment": "16 pages", "categories": [ "math.AP" ], "abstract": "It is known that solutions to second order uniformly elliptic and parabolic equations, either in divergence or nondivergence (general) form, are H\\\"{o}lder continuous and satisfy the interior Harnack inequality. We show that even in the one-dimensional case ($x\\in R^1$), these properties are not preserved for equations of mixed divergence-nondivergence structure: for elliptic equations. \\begin{equation*} D_i(a^1_{ij}D_ju)+a^2_{ij}D_{ij}u=0, \\end{equation*} and parabolic equations \\begin{equation*} p\\partial_t u=D_i(a_{ij}D_ju), \\end{equation*} where $p=p(t,x)$ is a bounded strictly positive function. The H\\\"{o}lder continuity and Harnack inequality are known if $p$ does not depend either on $t$ or on $x$. We essentially use homogenization techniques in our construction. Bibliography: 23 titles.", "revisions": [ { "version": "v1", "updated": "2014-01-02T01:03:16.000Z" } ], "analyses": { "keywords": [ "parabolic equations", "second order elliptic", "mixed type", "second order uniformly elliptic", "interior harnack inequality" ], "note": { "typesetting": "TeX", "pages": 16, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1401.0351C" } } }