{ "id": "1202.2674", "version": "v2", "published": "2012-02-13T09:46:03.000Z", "updated": "2013-03-22T09:55:37.000Z", "title": "$L^{\\infty}$ estimates and uniqueness results for nonlinear parabolic equations with gradient absorption terms", "authors": [ "Marie-Françoise Bidaut-Véron", "Nguyen Anh Dao" ], "categories": [ "math.AP" ], "abstract": "Here we study the nonnegative solutions of the viscous Hamilton-Jacobi problem \\[ \\left\\{\\begin{array} [c]{c}% u_{t}-\\nu\\Delta u+|\\nabla u|^{q}=0, u(0)=u_{0}, \\end{array} \\right. \\] in $Q_{\\Omega,T}=\\Omega\\times\\left(0,T\\right) ,$ where $q>1,\\nu\\geqq 0,T\\in\\left(0,\\infty\\right] ,$ and $\\Omega=\\mathbb{R}^{N}$ or $\\Omega$ is a smooth bounded domain, and $u_{0}\\in L^{r}(\\Omega),r\\geqq1,$ or $u_{0}% \\in\\mathcal{M}_{b}(\\Omega).$ We show $L^{\\infty}$ decay estimates, valid for \\textit{any weak solution}, \\textit{without any conditions a}s $\\left\\| x\\right\\| \\rightarrow\\infty,$ and \\textit{without uniqueness assumptions}. As a consequence we obtain new uniqueness results, when $u_{0}\\in \\mathcal{M}_{b}(\\Omega)$ and $q<(N+2)/(N+1),$ or $u_{0}\\in L^{r}(\\Omega)$ and $q<(N+2r)/(N+r).$ We also extend some decay properties to quasilinear equations of the model type \\[ u_{t}-\\Delta_{p}u+\\left\\| u\\right\\| ^{\\lambda-1}u|\\nabla u|^{q}=0 \\] where $p>1,\\lambda\\geqq0,$ and $u$ is a signed solution.", "revisions": [ { "version": "v2", "updated": "2013-03-22T09:55:37.000Z" } ], "analyses": { "keywords": [ "nonlinear parabolic equations", "gradient absorption terms", "uniqueness results", "model type", "smooth bounded domain" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1202.2674B" } } }