Results 21 to 30 of about 601 (93)

UNBOUNDED 2-HYPEREXPANSIVE OPERATORS

Proceedings of the Edinburgh Mathematical Society, 2001
It is shown that most properties of (bounded) completely hyperexpansive operators remain valid for unbounded $2$-hyperexpansive operators. Powers of closed $2$-hyperexpansive operators are proved to be closed and $2$-hyperexpansive.
Z. Jablonski, J. Stochel
semanticscholar   +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

Spectrally two-uniform frames for erasures

, 2015
We continue to work on the problem of characterizing erasure-optimal frames when spectral radius is used as a measurement of the error operator. Spectrally optimal (N,n) -frames for one erasures are the ones that the minimal spectral error n/N can be ...
Saliha Pehlivan, D. Han, R. Mohapatra
semanticscholar   +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

On operators satisfying an inequality

Journal of Inequalities and Applications, 2012
An operator T is said to be k-quasi-∗-class A if T∗k(|T2|−|T∗|2)Tk≥0, where k is a natural number. Let dA,B∈B(B(H)) denote either the generalized derivation δA,B=LA−RB or the elementary operator ΔA,B=LARB−I, where LA and RB are the left and right ...
S. Mécheri
semanticscholar   +2 more sources

Fourier analysis, Schur multipliers on $S^p$ and non-commutative Λ(p)-sets

, 1999
This work deals with various questions concerning Fourier multipliers on L, Schur multipliers on the Schatten class S as well as their completely bounded versions when L and S are viewed as operator spaces.
A. Harcharras
semanticscholar   +1 more source

UNBOUNDEDNESS OF THE BERGMAN PROJECTIONS ON $L^{p}$ SPACES WITH EXPONENTIAL WEIGHTS

Proceedings of the Edinburgh Mathematical Society, 2004
We prove that the Bergman projection on $L^p(w)$ $(p\neq 2)$, where $w(r)=(1-r^2)^A\textrm{e}^{-B/(1-r^2)^{\alpha}}$, is not bounded.
M. Dostanic
semanticscholar   +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

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

The invariant subspace problem for absolutely p-summing operators in Krein spaces

Journal of Inequalities and Applications, 2012
Let 1 ...
G. Wanjala
semanticscholar   +2 more sources