Some functional equations on standard operator algebras

Acta Mathematica Academiae Scientiarum Hungarica - Tập 118 - Trang 299-306 - 2007
A. Fošner1, J. Vukman1
1Department of Mathematics and Computer Science, Faculty of Natural Sciences and Mathematics, University of Maribor, Maribor, Slovenia

Tóm tắt

The main purpose of this paper is to prove the following result. Let H be a complex Hilbert space, let $$ \mathcal{B} $$ (H) be the algebra of all bounded linear operators on H, and let $$ \mathcal{A} $$ (H) ⊂ $$ \mathcal{B} $$ (H) be a standard operator algebra which is closed under the adjoint operation. Suppose that T: $$ \mathcal{A} $$ (H) → $$ \mathcal{B} $$ (H) is a linear mapping satisfying T(AA* A) = T(A)A* A − AT(A*)A + AA*T(A) for all A ∈ $$ \mathcal{A} $$ (H). Then T is of the form T(A) = AB + BA for all A ∈ $$ \mathcal{A} $$ (H), where B is a fixed operator from $$ \mathcal{B} $$ (H). A result concerning functional equations related to bicircular projections is proved

Tài liệu tham khảo

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