Nonradiality of second eigenfunctions of the fractional Laplacian in a ball
arXiv:2102.08298 · doi:10.1090/proc/16062
Abstract
Using symmetrization techniques, we show that, for every , any second eigenfunction of the fractional Laplacian in the -dimensional unit ball with homogeneous Dirichlet conditions is nonradial, and hence its nodal set is an equatorial section of the ball.
14 pages, 2 figures. Minor improvements according to the referee's suggestions. In particular, a couple of references were added and Lemma 2.1 was strengthened. Accepted to Proceedings of the AMS