Leaky quantum graphs: approximations by point interaction Hamiltonians

P. Exner, K. Nemcova

We prove an approximation result showing how operators of the type $-\Delta -\gamma \delta (x-\Gamma )$ in $L^2({\mathbb{R}}^2)$, where $\Gamma$ is a graph, can be modeled in the strong resolvent sense by point-…