A Kadison–sakai Type Theorem
نویسنده
چکیده
The celebrated Kadison–Sakai theorem states that every derivation on a von Neumann algebra is inner. In this paper, we prove this theorem for ultraweakly continuous ∗-σ-derivations, where σ is an ultraweakly continuous surjective ∗-linear mapping. We decompose a σ-derivation into a sum of an inner σ-derivation and a multiple of a homomorphism. The so-called ∗-(σ, τ)-derivations are also discussed.
منابع مشابه
A Generalization of the Kadison-sakai Theorem
The celebrated Kadison-Sakai Theorem states that all derivations on von Neumann algebras are inner. In this paper, we generalize this theorem to the so-called ∗-σderivations where σ is a weakly continuous ∗-linear mapping. We decompose a σ-derivation into a sum of an inner σ-derivation and a multiple of a homomorphism. As a consequence, we establish an extension of the Singer-Wermer Theorem. A ...
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تاریخ انتشار 2008