Spectrum of manifolds with holes
The author studies the spectrum of a bounded Euclidean domain \(X\) with a compact subset of small capacity removed. In particular he shows that there is a perturbation theory for the Dirichlet spectrum of \(X \setminus A\) where \(A\) is any ``small'' compact subset of \(X\) and the ``parameter'' of the perturbation is the capacity of \(A\) itself.
scientific article; zbMATH DE number 847469