Additive mappings on C ∗ -algebras sub-preserving absolute values of products

Springer Science and Business Media LLC - Tập 2012 - Trang 1-6 - 2012
Ali Taghavi1
1Department of Mathematics, Faculty of Mathematical Sciences, University of Mazandaran, Babolsar, Iran

Tóm tắt

Let be a -algebra of real rank zero and be a -algebra with unit I. It is shown that if is an additive mapping which satisfies for every and for some with , then the restriction of mapping ϕ to is a Jordan homomorphism, where denotes the set of all self-adjoint elements. We will also show that if ϕ is surjective preserving the product and an absolute value, then ϕ is a -linear or -antilinear ∗-homomorphism on . MSC:47B49, 46L05, 47L30.

Tài liệu tham khảo

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