Chi-Kwong Li

activity

20242026

collaborators

3 papers

math.CO2026

Cliques and independent subgroups of the Birkhoff polytope graph

Zejun Huang, Chi-Kwong Li, Eric Swartz +1

The Birkhoff polytope $I^c ◯_{n}$ is the polytope of doubly stochastic matrices of order $n$ . The Birkhoff polytope graph $G (I^c ◯_{n})$ is the skeleton of $I^c ◯_{n}$ ; it is the Cayley graph who…

math.NA2025

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 $N$ -by-$…

quant-ph2024

A note on Majorana representation of quantum states

Chi-Kwong Li, Mikio Nakahara

By the Majorana representation, for any $d > 1$ there is a one-one correspondence between a quantum state of dimension $d$ and $d - 1$ qubits represented as $d - 1$ points in the Bloch…