A definition of numerical range of rectangular matrices

Chorianopoulos, C; Karanasios, S; Psarrakos, P

dc.contributor.author	Chorianopoulos, C	en
dc.contributor.author	Karanasios, S	en
dc.contributor.author	Psarrakos, P	en
dc.date.accessioned	2014-03-01T01:29:32Z
dc.date.available	2014-03-01T01:29:32Z
dc.date.issued	2009	en
dc.identifier.issn	0308-1087	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/19291
dc.subject	Birkhoff-James orthogonality	en
dc.subject	Norm	en
dc.subject	Numerical range	en
dc.subject.classification	Mathematics	en
dc.subject.other	PENCILS	en
dc.title	A definition of numerical range of rectangular matrices	en
heal.type	journalArticle	en
heal.identifier.primary	10.1080/03081080802466365	en
heal.identifier.secondary	http://dx.doi.org/10.1080/03081080802466365	en
heal.language	English	en
heal.publicationDate	2009	en
heal.abstract	Bonsall and Duncan (1973) observed that the numerical range of a bounded linear operator can be written as an infinite intersection of closed circular discs. Motivated by this interesting property (which does not seem to be very popular with people working on numerical ranges), we propose a definition of numerical range of rectangular complex matrices. The new range is always compact and convex, and satisfies basic properties of the standard numerical range. Our analysis is based on the properties of norms and the Birkhoff-James orthogonality. © 2009 Taylor & Francis.	en
heal.publisher	TAYLOR & FRANCIS LTD	en
heal.journalName	Linear and Multilinear Algebra	en
dc.identifier.doi	10.1080/03081080802466365	en
dc.identifier.isi	ISI:000268237100004	en
dc.identifier.volume	57	en
dc.identifier.issue	5	en
dc.identifier.spage	459	en
dc.identifier.epage	475	en