Spectrum and commutativity preserving mappings on \(H _{2}\)
The description of continuous (linear) mapping on the real symmetric or complex Hermitian \(2\times 2\)-matrices, preserving the spectrum and commutativity properties, is given. The paper is based on the previous works of \textit{T. Petek} and \textit{P. Šemrl} [ibid. 269, 33-46 (1998; Zbl 0891.15001)] and of \textit{T. Petek} [ibid. 290, 167-191 (1999; Zbl 0930.15027)], related to the case of \(3\times 3\)-matrices.
scientific article; zbMATH DE number 1903592