{"title":"Weyl asymptotics for fractional-order Dirichlet realizations in nonsmooth cases","authors":"Gerd Grubb","doi":"10.7146/math.scand.a-138002","DOIUrl":null,"url":null,"abstract":"Let $P$ be a symmetric $2a$-order classical strongly elliptic pseudodifferential operator with \\emph{even} symbol $p(x,\\xi)$ on $\\mathbb{R}^n $ ($0<a<1$), for example a perturbation of $(-\\Delta )^a$. Let $\\Omega \\subset \\mathbb{R}^n$ be bounded, and let $P_D$ be the Dirichlet realization in $L_2(\\Omega)$ defined under the exterior condition $u=0$ in $\\mathbb{R}^n\\setminus\\Omega$. When $p(x,\\xi)$ and $\\Omega$ are $C^\\infty $, it is known that the eigenvalues $\\lambda_j$ (ordered in a nondecreasing sequence for $j\\to \\infty$) satisfy a Weyl asymptotic formula \\begin{equation*} \\lambda _j(P_{D})=C(P,\\Omega )j^{2a/n}+o(j^{2a/n}) \\text {for $j\\to \\infty $}, \\end{equation*} with $C(P,\\Omega)$ determined from the principal symbol of $P$. We now show that this result is valid for more general operators with a possibly nonsmooth $x$-dependence, over Lipschitz domains, and that it extends to $\\tilde P=P+P'+P”$, where $P'$ is an operator of order $<\\min\\{2a, a+\\frac 12\\}$ with certain mapping properties, and $P”$ is bounded in $L_2(\\Omega )$ (e.g. $P”=V(x)\\in L_\\infty(\\Omega)$). Also the regularity of eigenfunctions of $P_D$ is discussed.","PeriodicalId":0,"journal":{"name":"","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.7146/math.scand.a-138002","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 1
Abstract
Let $P$ be a symmetric $2a$-order classical strongly elliptic pseudodifferential operator with \emph{even} symbol $p(x,\xi)$ on $\mathbb{R}^n $ ($0