Hilbert space theory and operator algebras provide a robust framework for analysing linear operators and their spectral properties, which are pivotal in both pure and applied mathematics. Hilbert ...

Let E be an arbitrary set and F(E) a linear space composed of all complex valued functions on E. Let H be a (possibly finite-dimensional) Hilbert space with inner product (,)H. Let h: E → H be a ...

In this paper we determine the relationship between the spectra of a continuous contraction semigroup on Hilbert space and properties of the resolvent of its infinitesimal generator. The methods rely ...