The EMS Publishing House is now EMS Press and has its new home at

Please find all EMS Press journals and articles on the new platform.

Zeitschrift für Analysis und ihre Anwendungen

Full-Text PDF (158 KB) | Abstract as PDF | Metadata | Table of Contents | ZAA summary
Volume 23, Issue 2, 2004, pp. 303–311
DOI: 10.4171/ZAA/1200

Published online: 2004-06-30

Another Version of Maher's Inequality

Salah Mecheri[1]

(1) King Saud University, Riyadh, Saudi Arabia

Let $H$ be a separable infinite dimensional complex Hilbert space, and let $ L(H)$ denote the algebra of bounded linear operators on $H$ into itself. Let $ A=(A_{1},A_{2}...,A_{n})$, $B =(B_{1},B_{2}...,B_{n})$ be n-tuples of operators in $L(H)$. We define the elementary operator $\Delta _{A,B}: L(H) \mapsto L(H)$ by $\Delta _{A,B}(X)=\sum_{i=1}^{n}A_{i}XB_{i}-X.$ In this paper we minimize the map $F_{p}(X)= \left\| T -\Delta _{A,B}(X) \right\| _{p}^{p}$, where $T\in \ker\Delta _{A,B}\cap C_{p}$, and we classify its critical points.

Keywords: Orthogonality, derivation, elementary operators

Mecheri Salah: Another Version of Maher's Inequality. Z. Anal. Anwend. 23 (2004), 303-311. doi: 10.4171/ZAA/1200