3 papers
math.FA2021
Quantifying shrinking and boundedly complete bases
Dongyang Chen, Tomasz Kania, Yingbin Ruan
We investigate possible quantifications of R. C. James' classical work on bases and reflexivity of Banach spaces. By introducing new quantities measuring how far a basic sequence i…
math.FA2021
Quantifying properties () and ()
Dongyang Chen, Tomasz Kania, Yingbin Ruan
A Banach space has \textit{property }, whenever every weak* null sequence in the dual space admits a convex block subsequence so that $\langle f_{n}…
math.FA2021
Positively -nuclear operators, positively -integral operators and approximation properties
Dongyang Chen, Amar Belacel, Javier Alejandro Chávez-Domínguez
In the present paper, we introduce and investigate a new class of positively -nuclear operators that are positive analogues of right -nuclear operators. One of our main resul…