Cartesian decompositions and Schatten norms
Let \(T\) be a Hilbert space operator with \(T=A+iB\), where \(A\) and \(B\) are Hermitian. The authors establish the sharp inequalities comparing the norms \(\|T\|_p\) with \(\|(A^2+B^2)^{1/2}\|_p\) and \((\|A\|_p^2+\|B\|_p^2)^{1/2}\), where \(\|\cdot\|_p\) is the Schatten \(p\)-norm.
scientific article; zbMATH DE number 1547891