Operators with extension property and the principle of local reflexivity
Perturbation of a Fredholm complex by inessential operators.
Perturbation of the spectrum οf an essentially selfadjoint operator
The aim of this paper is to find estimates of the Hausdorff distance between the spectra of two nonselfadjoint operators. The operators considered are assumed to have their imaginary parts in some normed ideal of compact operators. In the case of the classical Schatten ideals the estimates are given explicitly.
Quantitative estimates for interpolated operators by multidimensional methods.
We describe the behavior of ideal variations under interpolation methods associated to polygons.
Quasi-normed operator ideals on Banach spaces and interpolation.
Remarks on embeddable semigroups in groups and a generalization of some Cuthbert's results.
Sharp uniform convexity and smoothness inequalities for trace norms.
Some extensions on the Sadovskii functor.
Some Relations Between s-Numbers of Operators on Banach Spaces.
Some remarks on the uniform approximation property in Banach spaces
Some stable operator ideals
Some stable operator ideals.
Some stable operator ideals
Sur quelques extensions au cadre banachique de la notion d'opérateur de Hilbert-Schmidt
In this work we discuss several ways to extend to the context of Banach spaces the notion of Hilbert-Schmidt operator: p-summing operators, γ-summing or γ-radonifying operators, weakly* 1-nuclear operators and classes of operators defined via factorization properties. We introduce the class PS₂(E;F) of pre-Hilbert-Schmidt operators as the class of all operators u: E → F such that w ∘ u ∘ v is Hilbert-Schmidt for every bounded operator v: H₁ → E and every bounded operator w: F → H₂, where H₁ and...
Surjective factorization of holomorphic mappings
We characterize the holomorphic mappings between complex Banach spaces that may be written in the form , where is another holomorphic mapping and belongs to a closed surjective operator ideal.
The associated tensor norm to -absolutely summing operators on -spaces
We give an explicit description of a tensor norm equivalent on to the associated tensor norm to the ideal of -absolutely summing operators. As a consequence, we describe a tensor norm on the class of Banach spaces which is equivalent to the left projective tensor norm associated to .
The ideal of p-compact operators: a tensor product approach
We study the space of p-compact operators, , using the theory of tensor norms and operator ideals. We prove that is associated to , the left injective associate of the Chevet-Saphar tensor norm (which is equal to ). This allows us to relate the theory of p-summing operators to that of p-compact operators. Using the results known for the former class and appropriate hypotheses on E and F we prove that is equal to for a wide range of values of p and q, and show that our results are sharp....
The impact of the Radon-Nikodym property on the weak bounded approximation property.
A Banach space X is said to have the weak λ-bounded approximation property if for every separable reflexive Banach space Y and for every compact operator T : X → Y, there exists a net (Sα) of finite-rank operators on X such that supα ||TSα|| ≤ λ||T|| and Sα → IX uniformly on compact subsets of X.We prove the following theorem. Let X** or Y* have the Radon-Nikodym property; if X has the weak λ-bounded approximation property, then for every bounded linear operator T: X → Y, there exists a net (Sα)...
Topologies and bornologies determined by operator ideals, II
Let be an operator ideal on LCS’s. A continuous seminorm p of a LCS X is said to be - continuous if , where is the completion of the normed space and is the canonical map. p is said to be a Groth()- seminorm if there is a continuous seminorm q of X such that p ≤ q and the canonical map belongs to . It is well known that when is the ideal of absolutely summing (resp. precompact, weakly compact) operators, a LCS X is a nuclear (resp. Schwartz, infra-Schwartz) space if and only if every continuous...
Type and cotype numbers of operators on Banach spaces