On extreme contractions and vertices in operator spaces
Volume 178 / 2025
Colloquium Mathematicum 178 (2025), 123-130
MSC: Primary 46B20; Secondary 46B25, 46A32
DOI: 10.4064/cm9442-3-2025
Published online: 12 May 2025
Abstract
The investigations of the extreme points of the closed unit ball in spaces of operators were started by Kadison (1954) considering the operator space $\mathcal L(H)$. Grząślewicz (1997) considered the vertices of subsets of $\mathcal L(H)$. In this paper, motivated by more recent results, we investigate the extreme points and vertices in $\mathcal L(\ell _{\infty }^n,\ell _{1}^m)$, $\mathcal L(c_0,\ell _{1})$ and $\mathcal L(\ell _{1})$.
