Unitary equivalence of proper extensions of a symmetric operator and the Weyl function

Seppo Hassi, Mark Malamud, Vadim Mogilevskii

Let $A$ be a densely defined simple symmetric operator in $\gH$, let $Π=\bt$ be a boundary triplet for $A^{\ast }$ and let $M(\cd)$ be the corresponding Weyl function. It is known that t…