Ya-Shu Wang

collaborators

Showing math.FAShow all

3 papers · 1 filter

math.FA2024

Linear maps preserving $ℓ_{p}$ -norm parallel vectors

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

Two vectors $x, y$ in a normed vector space are parallel if there is a scalar $μ$ with $∣ μ ∣ = 1$ such that $∥ x + μ y ∥ = ∥ x ∥ + ∥ y ∥$ ; they form a triangle equality attaining (TEA)…

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.FA2012

Compact and weakly compact disjointness preserving operators on spaces of differentiable functions

Denny H. Leung, Ya-Shu Wang

A pair of functions defined on a set X with values in a vector space E is said to be disjoint if at least one of the functions takes the value 0 at every point in X. An operator ac…

Linear maps preserving ℓp​-norm parallel vectors

Linear maps preserving matrices annihilated by a fixed polynomial

Compact and weakly compact disjointness preserving operators on spaces of differentiable functions

Linear maps preserving $ℓ_{p}$ -norm parallel vectors