Continuity of Operator Functions in the Topology of Local Convergence in Measure

A. M. Bikchentaev ; O. E. Tikhonov

Informatics and Automation, Noncommutative Analysis and Quantum Information Theory, Tome 324 (2024), pp. 51-59

Résumé

Let a von Neumann algebra $\mathcal M$ of operators act on a Hilbert space $\mathcal {H}$, and let $\tau $ be a faithful normal semifinite trace on $\mathcal M$. Let $t_{\tau \textup {l}}$ be the topology of $\tau $-local convergence in measure on the *-algebra $S(\mathcal M,\tau )$ of all $\tau $-measurable operators. We prove the $t_{\tau \textup {l}}$-continuity of the involution on the set of all normal operators in $S(\mathcal M,\tau )$, investigate the $t_{\tau \textup {l}}$-continuity of operator functions on $S(\mathcal M,\tau )$, and show that the map $A\mapsto |A|$ is $t_{\tau \textup {l}}$-continuous on the set of all partial isometries in $\mathcal M$.

Détail

Keywords: Hilbert space, linear operator, von Neumann algebra, normal trace, measurable operator, local convergence in measure, continuity of operator functions.