Nodal domains a la Courant

A. Ancona, B. Helffer, T. Hoffmann-Ostenhof

Let $H(\Om_0)=-Δ+V$ be a Schrödinger operator on a bounded domain $\Om_0\subset \mathbb R^d$ with Dirichlet boundary conditions. Suppose that the $\Om_\ell$ ($\ell \in \{1,...,k\}$…