Gaps of operators
An operator on \(\mathbb{C}^2\otimes l_2(\mathbb{Z})\) is defined by a matrix where the only nonzero entries are two \(2\times 2\)-matrices shifted on the first subdiagonal, one of which is a diagonal matrix with two nonnegative eigenvalues. Varying the eigenvalues, examples are obtained to distinguish the classes of \(p\)-hyponormal, \(w\)-hyponormal and absolute-\(p\)-paranormal operators.
scientific article; zbMATH DE number 2157555