A CONSTRUCTION OF HERGLOTZ SPACES

  • Published : 2004.08.01

Abstract

Let W(z) be a power series with operator coefficients such that multiplication by W(z) is contractive in extC(z). The overlapping space $\varepsilon$(W) of D(W) in C(z) is a Herglotz space with Herglotz function $\varphi$(z) which satisfies $\varphi$(z) + ${\varphi}^*(z^{-1})$ = 2[1-W$^*(z^{-1})W(z)]$.