Sobre los espacios de Banach que contienen a l1 como complementado.
Sobre los operadores desplazamiento bilateral ponderados e invertibles.
In this paper the analytic-spectral structure of the commutant of an invertible bilateral weighted shift operator is studied, extending known results. A class of operators is introduced, more general than the class of the rationally strictly cyclic bilateral shift [operators] which are not unicellular.
Sobre los operadores desplazamiento ponderados sub-acotados.
We study the relation between the sets of cyclic vectors of an unilateral bounded below weighted shift operator T and T|S where S is an invariant subspace of T. It is proved that T can not be unicellular and known results are generalized.
Sobre operadores de integración fraccional y algoritmos computacionales
Solution d’un problème sur les itères d’un opérateur positif sur
Solvability conditions for some difference operators.
Solvability of boundary value problems for operator-differential equations of mixed type.
Some applications of functions of several complex variables to Toeplitz and subnormal operators
Some applications of p-summing operators to Banach space theory
Some Berezin number inequalities for operator matrices
Some Characterizations of AM- and AL-Spaces.
Some characterizations of order weakly compact operator
We introduce the notion of order weakly sequentially continuous lattice operations of a Banach lattice, use it to generalize a result regarding the characterization of order weakly compact operators, and establish its converse. Also, we derive some interesting consequences.
Some characterizations of weakly compact operator on Banach lattices
We establish necessary and sufficient conditions under which each operator between Banach lattices is weakly compact and we give some consequences.
Some classes of commuting n-tuples of operators
Some classical operators on Lorentz space.
Some conditions for a -semigroup to be asymptotically finite-dimensional.
Some counterexamples to subexponential growth of orthogonal polynomials
We give examples of polynomials p(n) orthonormal with respect to a measure μ on ⨍ such that the sequence {p(n,x)} has exponential lower bound for some points x of supp μ. Moreover, the set of such points is dense in the support of μ.
Some density theorems for Toeplitz operators on Bergman spaces
Some duality results on bounded approximation properties of pairs
The main result is as follows. Let X be a Banach space and let Y be a closed subspace of X. Assume that the pair has the λ-bounded approximation property. Then there exists a net of finite-rank operators on X such that and for all α, and and converge pointwise to the identity operators on X and X*, respectively. This means that the pair (X,Y) has the λ-bounded duality approximation property.
Some eigenvalue estimates for wavelet related Toeplitz operators
By a straightforward computation we obtain eigenvalue estimates for Toeplitz operators related to the two standard reproducing formulas of the wavelet theory. Our result extends the estimates for Calderón-Toeplitz operators obtained by Rochberg in [R2]. In the first section we recall two standard reproducing formulas of the wavelet theory, we define Toeplitz operators and discuss some of their properties. The second section contains precise statements of our results and their proofs. At the end...