Results 11 to 20 of about 53 (53)
Functions of self‐adjoint operators in ideals of compact operators
Journal of the London Mathematical Society, Volume 95, Issue 1, Page 157-176, February 2017., 2017 Abstract For self‐adjoint operators A,B, a bounded operator J, and a function f:R→C, we obtain bounds in quasi‐normed ideals of compact operators for the difference f(A)J−Jf(B) in terms of the operator AJ−JB. The focus is on functions f that are smooth everywhere except for finitely many points. A typical example is the function f(t)=|t|γ with γ∈(0,1).
Alexander V. Sobolev
wiley +1 more source
Extension of Zhu′s solution to Lotto′s conjecture on the weighted Bergman spaces
International Journal of Mathematics and Mathematical Sciences, Volume 2004, Issue 41, Page 2199-2203, 2004., 2004 We reformulate Lotto′s conjecture on the weighted Bergman space Aα2 setting and extend Zhu′s solution (on the Hardy space H2) to the space Aα2.
Abebaw Tadesse
wiley +1 more source
Interpolation methods to estimate eigenvalue distribution of some integral operators
International Journal of Mathematics and Mathematical Sciences, Volume 2004, Issue 9, Page 479-485, 2004., 2004 We study the asymptotic distribution of eigenvalues of integral operators Tk defined by kernels k which belong to Triebel‐Lizorkin function space Fpuσ(F qvτ) by using the factorization theorem and the Weyl numbers xn. We use the relation between Triebel‐Lizorkin space Fpuσ(Ω) and Besov space Bpqτ(Ω) and the interpolation methods to get an estimation ...
E. M. El-Shobaky +3 more
wiley +1 more source
Uniformly summing sets of operators on spaces of continuous functions
International Journal of Mathematics and Mathematical Sciences, Volume 2004, Issue 63, Page 3397-3407, 2004., 2004 Let X and Y be Banach spaces. A set ℳ of 1‐summing operators from X into Y is said to be uniformly summing if the following holds: given a weakly 1‐summing sequence (xn) in X, the series ∑n‖Txn‖ is uniformly convergent in T ∈ ℳ. We study some general properties and obtain a characterization of these sets when ℳ is a set of operators defined on spaces ...
J. M. Delgado, Cándido Piñeiro
wiley +1 more source
Some versions of Anderson′s and Maher′s inequalities I
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 52, Page 3281-3297, 2003., 2003 We prove the orthogonality (in the sense of Birkhoff) of the range and the kernel of an important class of elementary operators with respect to the Schatten p‐class.
Salah Mecheri
wiley +1 more source
Some versions of Anderson′s and Maher′s inequalities II
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 53, Page 3355-3372, 2003., 2003 We are interested in the investigation of the orthogonality (in the sense of Birkhoff) of the range of an elementary operator and its kernel.
Salah Mecheri
wiley +1 more source
Generalized derivation modulo the ideal of all compact operators
International Journal of Mathematics and Mathematical Sciences, Volume 32, Issue 8, Page 501-506, 2002., 2002 We give some results concerning the orthogonality of the range and the kernel of a generalized derivation modulo the ideal of all compact operators.
Salah Mecheri, Ahmed Bachir
wiley +1 more source
Ornstein-Uhlenbeck processes in Banach spaces and their spectral representations. [PDF]
, 2002 For Q the variance of some centred Gaussian random vector in a separable Banach space it is shown that, necessarily, Q factors through $\ell^2$ as a product of 2-summing operators.
James S. Groves, Groves, James S.
core +1 more source
A note on uniformly dominated sets of summing operators
International Journal of Mathematics and Mathematical Sciences, Volume 29, Issue 5, Page 307-312, 2002., 2002 Let Y be a Banach space that has no finite cotype and p a real number satisfying 1 ≤ p < ∞. We prove that a set ℳ ⊂ Πp(X, Y) is uniformly dominated if and only if there exists a constant C > 0 such that, for every finite set {(xi, Ti) : i = 1, …, n} ⊂ X × ℳ, there is an operator T ∈ Πp(X, Y) satisfying πp(T) ≤ C and ‖Tixi‖ ≤ ‖Txi‖ for i = 1, …, n.
J. M. Delgado, C. Piñeiro
wiley +1 more source
Geometric properties of composition operators belonging to Schatten classes
International Journal of Mathematics and Mathematical Sciences, Volume 26, Issue 4, Page 239-248, 2001., 2001 We investigate the connection between the geometry of the image domain of an analytic function mapping the unit disk into itself and the membership of the composition operator induced by this function in the Schatten classes. The purpose is to provide solutions to Lotto′s conjectures and show a new compact composition operator which is not in any of ...
Yongsheng Zhu
wiley +1 more source