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摘要: |
令~$H$ 是复数域~$\mathbb{C}$ 上的~Hilbert 空间, $\mathcal{B}(H)$ 表示~$H$ 上所有有界线性算子构成的代数,
$C,D\in\mathcal{B}(H)$ 是任意两个固定算子. 本文利用算子分解的方法, 证明了可加映射~$\phi:\mathcal{B}(H)\to\mathcal{B}(H)$ 满足条件对任意~$A,B\in\mathcal B(H)$, $AB=C$ 蕴涵~$\phi(A)B+A\phi(B)=D$ 成立当且仅当存在算子~$T\in\mathcal B(H)$ 与数~$\lambda\in\mathbb{C}$ 使得$\phi(C)+\lambda C=D$ 且~$\phi(A)=AT-TA+\lambda A$ 对所有~$A\in\mathcal{B}(H)$ 成立. 该结果推广改进了已有的一些相关成果. |
关键词: 可加导子 局部导子 有界线性算子 Hilbert空间 |
DOI: |
分类号:O177.1 |
基金项目:国家自然科学基金项目(面上项目,重点项目,重大项目) |
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A new characterization of additive derivations on B(H) |
霄霏
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Abstract: |
Let $H$ be any complex Hilbert space and $\mathcal{B}(H)$ the algebra of all bounded linear operators on $H$, and let $C,D\in\mathcal{B}(H)$ be any two fixed operators. In this paper, by using operator block methods, we show that an additive map $\delta:\mathcal B(H)\rightarrow\mathcal{B}(H)$ satisfies that, for any $A,B\in\mathcal B(H)$, $AB=C$ implies $\phi(A)B+A\phi(B)=D$, if and only if there exists some $T\in\mathcal B(H)$ and $\lambda\in\mathbb{C}$ such that $\phi(C)+\lambda C=D$ and $\phi(A)=AT-TA+\lambda A$ for all $A\in\mathcal{B}(H)$. Our result generalizes and improves some known related ones. |
Key words: Additive derivations local derivations bounded linear operators Hilbert spaces |