Document Type : Research Paper


1 Department of Multimedia, Tabriz Islamic Art University, Tabriz, Iran.

2 Department of Mathematics, Sahand University of Technology, Sahand Street, Tabriz, Iran.


Let $A$ be a unital $C^{*}$-algebra which has a faithful state. If $\varphi:A\rightarrow A$ is a unital linear map which is bijective and invertibility preserving or surjective and spectral radius preserving, then $\varphi$ is a Jordan isomorphism. Also, we discuss other types of linear preserver maps on $A$.


Main Subjects

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