Authors
Citation
J. Dazord, ON THE C-NUMERICAL RANGE OF A MATRIX, Linear algebra and its applications, 212, 1994, pp. 21-29
Citations number
8
Categorie Soggetti
Mathematics,Mathematics
Journal title
ISSN journal
00243795
Volume
212
Year of publication
1994
Pages
21 - 29
Database
ISI
SICI code
0024-3795(1994)212:<21:OTCROA>2.0.ZU;2-P
Abstract
Given two n x n complex matrices C and T, we prove that if the differe
ntiable mapping q : U(n, C) --> R(2) defined by q(U) = tr(CUTU) is of
rank at most 1 on a nonempty open set, then the C-numerical range W(C
, T) of T is a line segment. The same conclusion holds whenever the in
terior of W(C, T) is empty.