Calculus of Variations and Geometric Measure Theory

L. Brasco - G. Franzina - B. Ruffini

Schrödinger operators with negative potentials and Lane-Emden densities

created by ruffini on 13 Apr 2017
modified on 10 Apr 2018


Published Paper

Inserted: 13 apr 2017
Last Updated: 10 apr 2018

Journal: J. Funct. Anal.
Pages: 29
Year: 2017


We consider the Schrödinger operator $-\Delta+V$ for negative potentials $V$, on open sets with positive fi rst eigenvalue of the Dirichlet-Laplacian. We show that the spectrum of $-\Delta+V$ is positive, provided that $V$ is greater than a negative multiple of the logarithmic gradient of the solution to the Lane-Emden equation $-\Delta u = u^{q-1}$ (for some $1\le q<2$). In this case, the ground state energy of $-\Delta+V$ is greater than the first eigenvalue of the Dirichlet-Laplacian, up to an explicit multiplicative factor. This is achieved by means of suitable Hardy-type inequalities, that we prove in this paper.