On the spectrum of orthomorphisms and Barbashin operators.
On the spectrum of the operator which is a composition of integration and substitution
Let ϕ: [0,1] → [0,1] be a nondecreasing continuous function such that ϕ(x) > x for all x ∈ (0,1). Let the operator be defined on L₂[0,1]. We prove that has a finite number of nonzero eigenvalues if and only if ϕ(0) > 0 and ϕ(1-ε) = 1 for some 0 < ε < 1. Also, we show that the spectral trace of the operator always equals 1.
On the surjectivity of linear transformations.
On the weighted estimate of the Bergman projection
We present a proof of the weighted estimate of the Bergman projection that does not use extrapolation results. This estimate is extended to product domains using an adapted definition of Békollé-Bonami weights in this setting. An application to bounded Toeplitz products is also given.
On totally -paranormal operators
In this paper we study some properties of a totally -paranormal operator (defined below) on Hilbert space. In particular, we characterize a totally -paranormal operator. Also we show that Weyl’s theorem and the spectral mapping theorem hold for totally -paranormal operators through the local spectral theory. Finally, we show that every totally -paranormal operator satisfies an analogue of the single valued extension property for and some of totally -paranormal operators have scalar extensions....
On typical Markov operators acting on Borel measures.
On uniformly smoothing stochastic operators
We show that a stochastic operator acting on the Banach lattice of all -integrable functions on is quasi-compact if and only if it is uniformly smoothing (see the definition below).
On Volterra composition operators from Bergman-type space to Bloch-type space
Let be an analytic self-mapping of and an analytic function on . In this paper we characterize the bounded and compact Volterra composition operators from the Bergman-type space to the Bloch-type space. We also obtain an asymptotical expression of the essential norm of these operators in terms of the symbols and .
On weak restricted estimates and endpoints problems for convolutions with oscillating kernels (II)
On weakly compact operators from some uniform algebras
One criterion for nuclearity of linear operators.
Operadores débilmente compactos e incondicionalmente convergentes en espacios de funciones continuas con valores vectoriales.
Operadores débilmente compactos en espacios de funciones continuas con valores vectoriales, y la propiedad de Radon-Nykodim.
Operadores sobre espacios de sucesiones infraperiódicas con valores vectoriales (II).
Opérateurs réguliers sur les espaces
Opérateurs sur un espace
Operator positivity and analytic models of commuting tuples of operators
We study analytic models of operators of class with natural positivity assumptions. In particular, we prove that for an m-hypercontraction on a Hilbert space , there exist Hilbert spaces and ⁎ and a partially isometric multiplier θ ∈ ℳ (H²(),A²ₘ(⁎)) such that and , where A²ₘ(⁎) is the ⁎-valued weighted Bergman space and H²() is the -valued Hardy space over the unit disc . We then proceed to study analytic models for doubly commuting n-tuples of operators and investigate their applications...
Operator theorems on -convergence to zero
Operators acting on certain Banach spaces of analytic functions.
Operators induced by transformations of Gaussian variables