Slow growth for universal harmonic functions.
Slowly decreasing entire functions and convolution equations
Slowly oscillating perturbations of periodic Jacobi operators in l²(ℕ)
We prove that the absolutely continuous part of the periodic Jacobi operator does not change (modulo unitary equivalence) under additive perturbations by compact Jacobi operators with weights and diagonals defined in terms of the Stolz classes of slowly oscillating sequences. This result substantially generalizes many previous results, e.g., the one which can be obtained directly by the abstract trace class perturbation theorem of Kato-Rosenblum. It also generalizes several results concerning perturbations...
Small functions and iterative methods
Iterative methods based on small functions are used both to show local surjectivity of certain operators and a fixed point property of mappings on scales of complete metric spaces.
Small sets and hypercyclic vectors
We study the ``smallness'' of the set of non-hypercyclic vectors for some classical hypercyclic operators.
Smooth operators and commutators
Smooth operators in the commutant of a contraction
For a completely non-unitary contraction T, some necessary (and, in certain cases, sufficient) conditions are found for the range of the calculus, , and the commutant, T’, to contain non-zero compact operators, and for the finite rank operators of T’ to be dense in the set of compact operators of T’. A sufficient condition is given for T’ to contain non-zero operators from the Schatten-von Neumann classes .
s-numbers of diagonal operators and Besov embeddings
s-Numbers of operators in Banach spaces
Sobczyk's theorem and the Bounded Approximation Property
Sobczyk's theorem asserts that every c₀-valued operator defined on a separable Banach space can be extended to every separable superspace. This paper is devoted to obtaining the most general vector valued version of the theorem, extending and completing previous results of Rosenthal, Johnson-Oikhberg and Cabello. Our approach is homological and nonlinear, transforming the problem of extension of operators into the problem of approximating z-linear maps by linear maps.
Sobolev- und Sobolev-Hardy-Räume auf S1: Dualitätstheorie und Funktionalkalküle.
Sobre Ciertos Espacios De Funciones Holo Morfas Y Sus Aplicaciones, II.
Sobre la ecuación cuadrática en operadores A + BT +TC + TDT = 0.
By means of the application of annihilating entire functions of an operator, the bilateral quadratic equation in operators A + BT +TC + TDT = 0, is changed into an unilateral linear equation, obtaining conditions under which the solutions of such linear equation satisfy the quadratic equation.
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
Sojourn times of trapping rays and the behavior of the modified resolvent of the laplacian
Solution d’un problème sur les itérés d’un opérateur positif sur et propriétés de moyennes associées
Soit un opérateur linéaire positif sur (où est un compact). On montre que si inf. , la suite des ) converge uniformément vers 0, et que si sup. la suite des converge uniformément vers .Puis on applique ces deux énoncés à l’étude des suites : et ; on donne en particulier plusieurs critères de convergence uniforme de ces suites.
Solution operators for convolution equations on the germs of analytic functions on compact convex sets in
is compact and convex it is known for a long time that the nonzero constant coefficients linear partial differential operators (of finite or infinite order) are surjective on the space of all analytic functions on G. We consider the question whether solutions of the inhomogeneous equation can be given in terms of a continuous linear operator. For instance we characterize those sets G for which this is always the case.
Solvability conditions for elliptic problems with non-Fredholm operators
The paper is devoted to solvability conditions for linear elliptic problems with non-Fredholm operators. We show that the operator becomes normally solvable with a finite-dimensional kernel on properly chosen subspaces. In the particular case of a scalar equation we obtain necessary and sufficient solvability conditions. These results are used to apply the implicit function theorem for a nonlinear elliptic problem; we demonstrate the persistence of travelling wave solutions to spatially periodic...
Solvability conditions for some difference operators.