Mapping cones of positive maps (2009)
We study cones of positive maps of B(H) into itself, i.e. cones which are closed under composition with completely positive maps. As applications we obtain characterizations of linear functionals...
Decomposable and atomic projection maps (2009)
It is shown that a trace invariant projection map, i.e. a positive unital idempotent map, of a finite dimensional C*-algebra into itself is non-decomposable if and only if it is atomic, or...
Cones of positive maps and their duality relations (2009)
Skowronek, Lukasz, Stormer, Erling, Zyczkowski, Karol
The structure of cones of positive and k-positive maps acting on a finite-dimensional Hilbert space is investigated. Special emphasis is given to their duality relations to the sets of superpositive...
Separable states and positive maps II (2008)
Using the natural duality between linear functionals on tensor products of C*-algebras with the trace class operators on a Hilbert space H and linear maps of the C*-algebra into B(H), we give two...
Asymptotic lifts of positive linear maps (2006)
Arveson, William, Stormer, Erling
We show that the notion of asymptotic lift generalizes naturally to normal positive maps $\phi$ acting on von Neumann algebras M. We focus on cases in which the domain of the asymptotic lift can be...
Multiplicative properties of positive maps (2006)
Let $\phi$ be a positive unital normal map of a von Neumann algebra $M$ into itself, and assume there is a family of normal $\phi$-invariant states which is faithful on the von Neumann algebra...
A reduction theorem for capacity of positive maps (2005)
We prove a reduction theorem for capacity of positive maps of finite dimensional C*-algebras, thus reducing the computation of capacity to the case when the image of a nonscalar projection is never a...
Ergodic theory and maximal abelian subalgebras of the hyperfinite factor (2001)
Neshveyev, Sergey, Stormer, Erling
Let T be a free ergodic measure-preserving action of an abelian group G on (X,mu). The crossed product algebra R_T has two distinguished masas, the image C_T of L^infty(X,mu) and the algebra S_T...
A survey of noncommutative dynamical entropy (2000)
The paper is a survey of dynamical entropy of automorphisms of operator algebras. We describe the different entropies of Connes-Stormer, Connes-Narnhofer-Thirring, Sauvageot-Thouvenot, and...
The variational principle for a class of asymptotically abelian C*-algebras (2000)
Neshveyev, Sergey, Stormer, Erling
Let (A,\alpha) be a C*-dynamical system. We introduce the notion of pressure P_\alpha(H) of the automorphism \alpha at a self-adjoint operator H\in A. Then we consider the class of AF-systems...
Entropy in type I algebras (2000)
Neshveyev, Sergey, Stormer, Erling
It is shown that if (M,phi,alpha) is a W*-dynamical system with M a type I von Neumann algebra then the entropy of alpha w.r.t. phi equals the entropy of the restriction of alpha to the center of M....