You-Qing Ji

collaborators

2 papers

math.FA2026

Asymptotic Numerical Ranges and Invariant Subspaces of Operators

Youqing Ji, Bangyuan Yang

For a bounded linear operator $T$ on a complex separable Hilbert space $H$ and a vector $x \in H$ , let $W_{a} (T, x)$ be the set of cluster points of the sequence $\…

math.FA2023

Power Set of Some Quasinilpotent Weighted shifts on $l^{p}$

Chaolong Hu, Youqing Ji

For a quasinilpotent operator $T$ on a Banach space $X$ , Douglas and Yang defined $k_{x} = z \to 0 lim sup \frac{l n ∥ ( z - T ) ^{- 1} x ∥}{l n ∥ ( z - T ) ^{- 1} ∥}$ for each nonzero…

Asymptotic Numerical Ranges and Invariant Subspaces of Operators

Power Set of Some Quasinilpotent Weighted shifts on lp

Power Set of Some Quasinilpotent Weighted shifts on $l^{p}$