Anderson, Joel and Foias, Ciprian (1975) Properties which normal operators share with normal derivations and related operators. Pacific Journal of Mathematics, 61 (2). pp. 313-325. ISSN 0030-8730 http://resolver.caltech.edu/CaltechAUTHORS:ANDpmj75
See Usage Policy.
Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:ANDpmj75
Let $S$ and $T$ be (bounded) scalar operators on a Banach space $\scr X$ and let $C(T,S)$ be the map on $\scr B(\scr X)$, the bounded linear operators on $\scr X$, defined by $C(T,S)(X)=TX-XS$ for $X$ in $\scr B(\scr X)$. This paper was motivated by the question: to what extent does $C(T,S)$ behave like a normal operator on Hilbert space? It will be shown that $C(T,S)$ does share many of the special properties enjoyed by normal operators. For example, it is shown that the range of $C(T,S)$ meets its null space at a positive angle and that $C(T,S)$ is Hermitian if $T$ and $S$ are Hermitian. However, if $\scr X$ is a Hilbert space then $C(T,S)$ is a spectral operator if and only if the spectrum of $T$ and the spectrum of $S$ are both finite.
|Additional Information:||Euclid Identifier: euclid.pjm/1102868028 Zentralblatt Math Identifier : 0324.47018 Mathmatical Reviews number (MathSciNet): MR0412889|
|Usage Policy:||No commercial reproduction, distribution, display or performance rights in this work are provided.|
|Deposited By:||Archive Administrator|
|Deposited On:||14 Jul 2005|
|Last Modified:||26 Dec 2012 08:40|
Repository Staff Only: item control page