{"title":"On a class of nonlocal obstacle type problems related to the distributional Riesz fractional derivative","authors":"Catharine Lo, J. Rodrigues","doi":"10.4171/PM/2100","DOIUrl":null,"url":null,"abstract":"In this work, we consider the nonlocal obstacle problem with a given obstacle $\\psi$ in a bounded Lipschitz domain $\\Omega$ in $\\mathbb{R}^{d}$, such that $\\mathbb{K}_\\psi^s=\\{v\\in H^s_0(\\Omega):v\\geq\\psi \\text{ a.e. in }\\Omega\\}\\neq\\emptyset$, given by \\[u\\in\\mathbb{K}_\\psi^s:\\langle\\mathcal{L}_au,v-u\\rangle\\geq\\langle F,v-u\\rangle\\quad\\forall v\\in\\mathbb{K}^s_\\psi,\\] for $F\\in H^{-s}(\\Omega)$, the dual space of $H^s_0(\\Omega)$, $0<s<1$. The nonlocal operator $\\mathcal{L}_a:H^s_0(\\Omega)\\to H^{-s}(\\Omega)$ is defined with a measurable, bounded, strictly positive singular kernel $a(x,y)$, possibly not symmetric, by \\[\\langle\\mathcal{L}_au,v\\rangle=P.V.\\int_{\\mathbb{R}^d}\\int_{\\mathbb{R}^d}v(x)(u(x)-u(y))a(x,y)dydx=\\mathcal{E}_a(u,v),\\] with $\\mathcal{E}_a$ being a Dirichlet form. Also, the fractional operator $\\tilde{\\mathcal{L}}_A=-D^s\\cdot AD^s$ defined with the distributional Riesz $s$-fractional derivative and a bounded matrix $A(x)$ gives a well defined integral singular kernel. The corresponding $s$-fractional obstacle problem converges as $s\\nearrow1$ to the obstacle problem in $H^1_0(\\Omega)$ with the operator $-D\\cdot AD$ given with the gradient $D$. We mainly consider problems involving the bilinear form $\\mathcal{E}_a$ with one or two obstacles, and the N-membranes problem, deriving a weak maximum principle, comparison properties, approximation by bounded penalization, and the Lewy-Stampacchia inequalities. This provides regularity of the solutions, including a global estimate in $L^\\infty(\\Omega)$, local H\\\"older regularity when $a$ is symmetric, and local regularity in $W^{2s,p}_{loc}(\\Omega)$ and $C^1(\\Omega)$ for fractional $s$-Laplacian obstacle-type problems. These novel results are complemented with the extension of the Lewy-Stampacchia inequalities to the order dual of $H^s_0(\\Omega)$ and some remarks on the associated $s$-capacity for general $\\mathcal{L}_a$.","PeriodicalId":51269,"journal":{"name":"Portugaliae Mathematica","volume":" ","pages":""},"PeriodicalIF":0.5000,"publicationDate":"2021-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"3","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Portugaliae Mathematica","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.4171/PM/2100","RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 3
Abstract
In this work, we consider the nonlocal obstacle problem with a given obstacle $\psi$ in a bounded Lipschitz domain $\Omega$ in $\mathbb{R}^{d}$, such that $\mathbb{K}_\psi^s=\{v\in H^s_0(\Omega):v\geq\psi \text{ a.e. in }\Omega\}\neq\emptyset$, given by \[u\in\mathbb{K}_\psi^s:\langle\mathcal{L}_au,v-u\rangle\geq\langle F,v-u\rangle\quad\forall v\in\mathbb{K}^s_\psi,\] for $F\in H^{-s}(\Omega)$, the dual space of $H^s_0(\Omega)$, $0
在这项工作中,我们考虑了在$\mathbb{R}^{d}$中有界Lipschitz域$\Omega$中给定障碍物$\psi$的非局部障碍问题,使得$\mathbb{K}_\psi^s=\{v\in H^s_0(\Omega):v\geq\psi\text{a.e.in}\Omega\}\neq\pemptyset$,由\[u\in\mathbb给出{K}_\psi ^s:\langle\mathcal{L}_au,v-u\rangle\geq\langle F,v-u\ rangle\quad\ for all v\in\mathbb{K}^s_\psi,\]对于$F\in H^{-s}(\Omega)$,$H^s_0(\Ome茄)$的对偶空间,$0
期刊介绍:
Since its foundation in 1937, Portugaliae Mathematica has aimed at publishing high-level research articles in all branches of mathematics. With great efforts by its founders, the journal was able to publish articles by some of the best mathematicians of the time. In 2001 a New Series of Portugaliae Mathematica was started, reaffirming the purpose of maintaining a high-level research journal in mathematics with a wide range scope.