An inverse spectral result for the Neumann operator on planar domains
The paper is about the Neumann operator, i.e. the operator transforming the Dirichlet condition to the Neumann condition for the Laplace equation. The author studies the spectrum of this operator and obtains the characterization of the unit disk.
operator transforming the Dirichlet condition to the Neumann condition for the Laplace equation
scientific article; zbMATH DE number 152044