Characterizing compact coincidence sets in the thin obstacle problem and the obstacle problem for the fractional Laplacian. (October 2021)

• Record Type: Journal Article
• Authors: Eberle, Simon; Ros-Oton, Xavier; Weiss, Georg S.
• Is Part Of: Nonlinear analysis. Volume 211(2021)
• Publication Date: 2021-10
• Subjects: Free boundary problems -- Global solutions -- Obstacle problem; Mathematical analysis -- Periodicals; Functional analysis -- Periodicals; Nonlinear theories -- Periodicals; Analyse mathématique -- Périodiques; Analyse fonctionnelle -- Périodiques; Théories non linéaires -- Périodiques; Functional analysis; Mathematical analysis; Nonlinear theories; Periodicals; Electronic journals; 515.7248
• DOI: 10.1016/j.na.2021.112473
• Languages: English
• ISSNs: 0362-546X

Abstract

Abstract: In this paper we give a full classification of global solutions of the obstacle problem for the fractional Laplacian (including the thin obstacle problem) with compact coincidence set and at most polynomial growth in dimension N ≥ 3 . We do this in terms of a bijection onto a set of polynomials describing the asymptotics of the solution. Furthermore we prove that coincidence sets of global solutions that are compact are also convex if the solution has at most quadratic growth.