On the M.Kac problem with augmented data

M. I. Belishev, A. F. Vakulenko

Let $\Omega$ be a bounded plane domain. As is known, the spectrum $0<{\lambda }_1<{\lambda }_2⩽\dots$ of its Dirichlet Laplacian $L=-\Delta \upharpoonright [H^2(\Omega )\cap H_0^1(\Omega )]$ does not determine $Ω…