The (𝒰 + 𝒦)-orbit of a Hilbert space operator T is defined as (𝒰 + 𝒦) (T) = {R−1TR : R invertible of the form unitary plus compact}. In previous work, P. S. Guinand and the present author have ...

John B. Conway, Paul McGuire, Operators with $C^\\ast$-Algebra Generated by a Unilateral Shift, Transactions of the American Mathematical Society, Vol. 284, No. 1 ...