Strict monotonicity of the first -eigenvalue of the fractional -Laplace operator over annuli
arXiv:2305.16672 · doi:10.1007/s12220-023-01539-9
Abstract
Let with be two balls such that and the position of is varied within . For , and with if and if , let be the first -eigenvalue of the fractional -Laplace operator in with the homogeneous nonlocal Dirichlet boundary conditions. We prove that strictly decreases as the inner ball moves towards the outer boundary . To obtain this strict monotonicity, we establish a strict Faber-Krahn type inequality for under polarization. This extends some monotonicity results obtained by Djitte-Fall-Weth (Calc. Var. Partial Differential Equations, 60:231, 2021) in the case of and to and Additionally, we provide the strict monotonicity results for the general domains that are difference of Steiner symmetric or foliated Schwarz symmetric sets in .
14 pages, 2 figures