Ya-Shu Wang

activity

20192024

most citedJoint numerical ranges and communtativity of matrices

1 citations · 2 across the 5 of their papers we have counts for

collaborators

5 papers

math.RA2024

Linear maps on matrices preserving parallel pairs

Chi-Kwong Li, Ming-Cheng Tsai, Ya-Shu Wang +1

Two (real or complex) $m \times n$ matrices $A$ and $B$ are said to be parallel (resp. triangle equality attaining, or TEA in short) with respect to the spectral norm $∥ \cdot ∥$ if…

math.FA2023

Linear maps preserving matrices annihilated by a fixed polynomial

Chi-Kwong Li, Ming-Cheng Tsai, Ya-Shu Wang +1

Let $M_{n} (F)$ be the algebra of $n \times n$ matrices over an arbitrary field $F$ . We consider linear maps $Φ: {\bf M}_n(\mathbb{F}) \rightarrow {\bf M}_r(\ma…

math.RA2020★ 1 cited

Nonsurjective zero product preservers between matrix spaces over an arbitrary field

Chi-Kwong Li, Ming-Cheng Tsai, Ya-Shu Wang +1

A map $Φ$ between matrices is said to be zero product preserving if $Φ (A) Φ (B) = 0 whenever A B = 0.$ In this paper, we give concrete descriptions of an additiv…

math.FA2020★ 1 cited

Joint numerical ranges and communtativity of matrices

Chi-Kwong Li, Yiu-Tung Poon, Ya-Shu Wang

The connection between the commutativity of a family of $n \times n$ matrices and the generalized joint numerical ranges is studied. For instance, it is shown that $F$ is a f…

math.RA2019

Nonsurjective maps between rectangular matrix spaces preserving disjointness, triple products, or norms

Chi-Kwong Li, Ming-Cheng Tsai, Ya-Shu Wang +1

Let $M_{m, n}$ be the space of $m \times n$ real or complex rectangular matrices. Two matrices $A, B \in M_{m, n}$ are disjoint if $A^{*} B = 0_{n}$ and $A B^{*} = 0_{m}$ . In this paper, a char…