A generalization of parallel addition.
A note on Banach algebras that are not isomorphic to a group algebra.
A note on extreme contractions on -spaces
A unified approach to the strong approximation property and the weak bounded approximation property of Banach spaces
We consider convex versions of the strong approximation property and the weak bounded approximation property and develop a unified approach to their treatment introducing the inner and outer Λ-bounded approximation properties for a pair consisting of an operator ideal and a space ideal. We characterize this type of properties in a general setting and, using the isometric DFJP-factorization of operator ideals, provide a range of examples for this characterization, eventually answering a question...
Approximation by Positive Operators.
Approximations of contraction operators on - I
Completely contractive maps between -algebras.
Criteria for Eberlein Compactness in Spaces of Continuous Functions.
Decomposability of extremal positive unital maps on M₂(ℂ)
A map φ: Mₘ(ℂ) → Mₙ(ℂ) is decomposable if it is of the form φ = φ₁ + φ₂ where φ₁ is a CP map while φ₂ is a co-CP map. It is known that if m = n = 2 then every positive map is decomposable. Given an extremal unital positive map φ: M₂(ℂ) → M₂(ℂ) we construct concrete maps (not necessarily unital) φ₁ and φ₂ which give a decomposition of φ. We also show that in most cases this decomposition is unique.
Directedness in Ordered Normed Spaces and Operators.
Exposed Points of the Unit Ball of ...(H).
Extremal Maps of a Hilbert Space Equipped with a Natural Cone.
Extreme Contraction Operators on l...
Extreme contractions on certain function spaces
Extreme Contractions on Real Hilbert Spaces.
Extreme operators on 2-dimensional -spaces
Extreme operators on AL-spaces
Extreme Points in Duals of Operator Spaces.
Extreme points in spaces of operators and vector – valued measures
Extreme positive contractions on the Hilbert space