2 problems

Let $H=-\Delta+V(x)$ act on $\mathbb{R}^{d}$, where $V$ is a potential satisfying … Here $\sigma_{ac}(H)$ denotes the absolutely continuous spectrum of $H$, and $\mathbb{R}^{+}$ de…

For even $\kappa\geq6$, define $J_3(\kappa)=(\cos(2\pi/\kappa),\cos^2(\pi/\kappa))$, and let $\boldsymbol{\mu}_{\kappa}(D)$ denote the absolutely-continuous-spectrum set defined in…