84 citations · 657 across the 85 of their papers we have counts for
87 papers
A Note on Eigenvalues of Perturbed Hermitian Matrices
Chi-Kwong Li, Ren-Cang Li
Let $$ A=\left(\begin{array}{cc} H_1 & E^*\\ E & H_2\end{array}\right) \quad \hbox{ and } \quad \wtd A=\left(\begin{array}{cc} H_1 & O\\ O & H_2\end{array}\right)$$ be two -by-$…
Linear maps preserving parallel matrix pairs with respect to the Ky-Fan -norm
Bojan Kuzma, Chi-Kwong Li, Edward Poon +1
Two bounded linear operators and are parallel with respect to a norm if for some scalar with . Characterization is obtai…
A note on Majorana representation of quantum states
Chi-Kwong Li, Mikio Nakahara
By the Majorana representation, for any there is a one-one correspondence between a quantum state of dimension and qubits represented as points in the Bloch…
On semidefinite programming characterizations of the numerical radius and its dual norm
Shmuel Friedland, Chi-Kwong Li
We state and give self contained proofs of semidefinite programming characterizations of the numerical radius and its dual norm for matrices. We show that the computation of the nu…
Numerical ranges of cyclic shift matrices
Mao-Ting Chien, Steve Kirkland, Chi-Kwong Li +1
We study the numerical range of an cyclic shift matrix, which can be viewed as the adjacency matrix of a directed cycle with weighted arcs. In particular, we consid…
Unified Derivation of Uncertainty Relations and Their Saturation Conditions
Chi-Kwong Li, Mikio Nakahara
We analyze uncertainty relations due to Kennard, Robertson, Schrödinger, Maccone and Pati in a unified way from matrix theory point of view. Short proofs are given to these uncerta…