Author : Adele Zucchi
Publisher : American Mathematical Soc.
Page : 52 pages
File Size : 40,8 Mb
Release : 1997
Category : Mathematics
ISBN : 9780821806265
Operators of Class C_0 with Spectra in Multiply Connected Regions by Adele Zucchi Pdf
Let $\Omega$ be a bounded finitely connected region in the complex plane, whose boundary $\Gamma$ consists of disjoint, analytic, simple closed curves. The author considers linear bounded operators on a Hilbert space $H$ having $\overline \Omega$ as spectral set, and no normal summand with spectrum in $\gamma$. For each operator satisfying these properties, the author defines a weak$^*$-continuous functional calculus representation on the Banach algebra of bounded analytic functions on $\Omega$. An operator is said to be of class $C_0$ if the associated functional calculus has a non-trivial kernel. In this work, the author studies operators of class $C_0$, providing a complete classification into quasisimilarity classes, which is analogous to the case of the unit disk.