Abstract
Given a convex domain C with conic boundary, a linear operator A with numerical range contained in , and a rational function bounded on , we are interested in estimating the norm of r(A) in terms of the supremum of r in . In particular, we show that ellipses, hyperbolas and parabolas are K-spectral sets with K = 2 + 2= p 3 3:16. 2000 Mathematical subject classications : 47A12 ; 47A25
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.