HALF-CENTERED OPERATORS

Artikel i vetenskaplig tidskrift, 2018

An operator T on a Hilbert space is called half-centered if the sequence T*T , (T*)T-2(2 ),... consists of mutually commuting operators. The class of such operators contains the well-studied class of centered operators. In this paper we give a criterion for when a half-centered operator is centered and prove a structure theorem for half-centered operators that satisfy some additional conditions.