Matrix Ordered Operator Algebras

Artikel i vetenskaplig tidskrift, 2009

We study the question when for a given *-algebra,A a sequence of cones C-n subset of M-n (A)(sa) can be realized as cones of positive operators in a faithful *-representation of A on a Hilbert space. We present a criterion analogous to Effros-Choi abstract characterization of operator systems. A characterization of operator algebras which are completely boundedly isomorphic to C*-algebras is also presented.