Results 241 to 250 of about 624,709 (272)

Linear Operators on Matrix Algebras that Preserve the Numerical Range, Numerical Radius or the States

Canadian Journal of Mathematics, 2004
AbstractEvery norm v on Cn induces two norm numerical ranges on the algebra Mn of all n × n complex matrices, the spatial numerical rangewhere vD is the norm dual to v, and the algebra numerical rangewhere is the set of states on the normed algebra Mn under the operator norm induced by v.
Li, Chi-Kwong, Sourour, Ahmed Ramzi
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Linear operators preserving the numerical range (radius) on triangular matrices

Linear and Multilinear Algebra, 2001
We characterize those linear operators on triangular or diagonal matrices preserving the numerical range or radius.
Chi-Kwong Li, Peter Šemrl, Graca Soares
openaire   +1 more source

Linear operators that preserve thec-numerical range or radius of matrices

Linear and Multilinear Algebra, 1988
Let For any n × n matrix A, define the c-numerical range and the c-numerical radius by and rc (A) = max{|z|: z∈ W c (A)} respectively. We give a characterization for those linear operators Twhich satisfy for all matrix A. Moreover, we give a full description for the extreme points of the unit ball in the real linear space of n × n hermitian matrices ...
Chi-Kwong Li, Nam-Kiu Tsing
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Duality between some linear preservers problems: the invariance of thec-numerical range, thec-numerical radius and certain matrix sets

Linear and Multilinear Algebra, 1988
Let C be a hermitian matrix. We show that the C-numerical range or C-numerical radius preservers are actually the dual operators of some matrix set preservers. We use the known results about the C-numerical range preservers to determine the structure of their dual operators.
Chi-Kwong Li, Nam-Kiu Tsing
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Weighted numerical range and weighted numerical radius for even-order tensor via Einstein product

Rendiconti del Circolo Matematico di Palermo Series 2
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Aaisha Be, Debasisha Mishra
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The invarianee ofC-numerical rangeC-numericai radius, and their dual problems

Linear and Multilinear Algebra, 1991
Let C be an n×n normal matrix. Let For any n×n matrix A, define the C-numerical range and the C-numerical radius of A by and respectively. We give a characierizaiion for those linear operators T which satisfy one of the following properties: .
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Numerical Ranges and Numerical Radius of Truncated Toeplitz Operators in the Case u = zn

International Journal of Mathematics Trends and Technology, 2023
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