二阶矩阵代数上的保谱半径的可加映射

Spectral Radius Preserving Additive Maps on 2×2 Matrix Algebras

获得了二阶复矩阵代数M2(C)上保谱半径的当且仅当Φ是同构、反同构、共轭同构或共轭反同构之一,从而补充完善了已知相应结果.

In this note we get a characteration of addtive maps preserving spectral radius on 2 × 2 matrix algebras, and prove Ф is an isomorphism, anti-isomorphism, Conjugate isomorphism or conjugate anti-isomorphism. Thus, complete a corresponding result in [2J.