Czechoslovak Mathematical Journal, Vol. 71, No. 3, pp. 817-822, 2021
On a Kleinecke-Shirokov theorem
Vasile Lauric
Received March 7, 2020. Published online March 8, 2021.
Abstract: We prove that for normal operators $N_1, N_2\in\mathcal{L(H)},$ the generalized commutator $[N_1, N_2; X]$ approaches zero when $[N_1,N_2; [N_1, N_2; X]]$ tends to zero in the norm of the Schatten-von Neumann class $\mathcal{C}_p$ with $p>1$ and $X$ varies in a bounded set of such a class.
Affiliations: Vasile Lauric, Department of Mathematics, Florida A& M University, 1601 S. Martin L. King Jr. Blvd., Tallahassee, FL 32307, USA, e-mail: vlauric@netzero.com