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A Kadison-Sakai Type Theorem

M. Mirzavaziri·M. S. Moslehian
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Abstract

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 σis 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.

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BibTeXRIS

M. Mirzavaziri, M. S. Moslehian. 2008-01-07. A Kadison-Sakai Type Theorem. https://arxiv.org/abs/math/0510267

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