Logo image
COMPLETE SPECTRAL SETS AND NUMERICAL RANGE
Journal article   Open access

COMPLETE SPECTRAL SETS AND NUMERICAL RANGE

Kenneth R. Davidson, Vern I. Paulsen and Hugo J. Woerdeman
Proceedings of the American Mathematical Society, v 146(3), pp 1189-1195
01 Mar 2018
url
https://doi.org/10.1090/proc/13801View
Accepted (AM)Open Access (Publisher-Specific) Open

Abstract

Mathematics, Applied Science & Technology Mathematics Physical Sciences
We define the complete numerical radius norm for homomorphisms from any operator algebra into B(H), and show that this norm can be computed explicitly in terms of the completely bounded norm. This is used to show that if K is a complete C- spectral set for an operator T, then it is a complete M- numerical radius set, where M = 1/2 (C + C-1). In particular, in view of Crouzeix's theorem, there is a universal constant M (less than 5.6) so that if P is a matrix polynomial and T is an element of B(H), then w(P(T)) = M <=parallel to P parallel to(W(T)). When W(T) = (D) over bar, we have M = 5/4.

Metrics

6 Record Views
5 citations in Scopus

Details

UN Sustainable Development Goals (SDGs)

This publication has contributed to the advancement of the following goals:

#11 Sustainable Cities and Communities

InCites Highlights

Data related to this publication, from InCites Benchmarking & Analytics tool:

Collaboration types
Domestic collaboration
International collaboration
Web of Science research areas
Mathematics
Mathematics, Applied
Logo image