Powers of class operators.
Powers of operators
Powers of -hyponormal operators.
Preassigning eigenvalues and zeros of nuclear operators
Precompactness in the uniform ergodic theory
We characterize the Banach space operators T whose arithmetic means form a precompact set in the operator norm topology. This occurs if and only if the sequence is precompact and the point 1 is at most a simple pole of the resolvent of T. Equivalent geometric conditions are also obtained.
Preconditioners and Korovkin-type theorems for infinite-dimensional bounded linear operators via completely positive maps
The classical as well as noncommutative Korovkin-type theorems deal with the convergence of positive linear maps with respect to different modes of convergence, like norm or weak operator convergence etc. In this article, new versions of Korovkin-type theorems are proved using the notions of convergence induced by strong, weak and uniform eigenvalue clustering of matrix sequences with growing order. Such modes of convergence were originally considered for the special case of Toeplitz matrices and...
Preservation of ergodicity under perturbation.
Preservation of ergodicity under perturbation (Erratum).
Preservation of tensor sum and tensor product.
Problème des moments matriciels sur la droite : construction d'une famille de solutions et questions d'unicité
Problems on Banach spaces
Processus abéliens associés à un semi-groupe.
Product of operators and numerical range preserving maps
Let V be the C*-algebra B(H) of bounded linear operators acting on the Hilbert space H, or the Jordan algebra S(H) of self-adjoint operators in B(H). For a fixed sequence (i₁, ..., iₘ) with i₁, ..., iₘ ∈ 1, ..., k, define a product of by . This includes the usual product and the Jordan triple product A*B = ABA as special cases. Denote the numerical range of A ∈ V by W(A) = (Ax,x): x ∈ H, (x,x) = 1. If there is a unitary operator U and a scalar μ satisfying such that ϕ: V → V has the form A...
Product spaces generated by bilinear maps and duality
In this paper we analyse a definition of a product of Banach spaces that is naturally associated by duality with a space of operators that can be considered as a generalization of the notion of space of multiplication operators. This dual relation allows to understand several constructions coming from different fields of functional analysis that can be seen as instances of the abstract one when a particular product is considered. Some relevant examples and applications are shown, regarding pointwise...
Products of commuting nilpotent operators.
Projection methods in the approximate solution of the eigenvalue problem in a Hilbert space
Projection Seminorms and the Field of Values of Linear Operators.
Projections, extendability of operators and the Gâteaux derivative of the norm.
Projections from a von Neumann algebra onto a subalgebra
Projections, skewness and related constants in real normed spaces.