The Block Numerical Range of an <i>n</i> × <i>n</i> Block Operator Matrix

Abstract

We introduce the new notion of the block numerical range for bounded n × n block operator matrices. The main results concern spectral inclusion, inclusion between block numerical ranges for refined block decompositions, an estimate of the resolvent in terms of the block numerical range, and block numerical ranges of companion operators.

Identifiers

DOI

10.1137/s0895479801394076

Citations and references