Classification, through coordinates, of M-bases in separable Banach spaces.
Closed categories and Banach spaces
Closed operator ideals and limiting real interpolation
We establish interpolation properties under limiting real methods for a class of closed ideals including weakly compact operators, Banach-Saks operators, Rosenthal operators and Asplund operators. We show that they behave much better than compact operators.
Closed subgroups in Banach spaces
We show that zero-dimensional nondiscrete closed subgroups do exist in Banach spaces E. This happens exactly when E contains an isomorphic copy of . Other results on subgroups of linear spaces are obtained.
CL-spaces and numerical radius attaining operators.
C-nearest points and the drop property.
Codimension one minimal projections in Banach spaces and a mathematical programming problem [Book]
Coefficient of orthogonal convexity of some Banach function spaces
We study orthogonal uniform convexity, a geometric property connected with property (β) of Rolewicz, P-convexity of Kottman, and the fixed point property (see [19, [20]). We consider the coefficient of orthogonal convexity in Köthe spaces and Köthe-Bochner spaces.
Coincidence of topologies on tensor products of Köthe echelon spaces
We investigate conditions under which the projective and the injective topologies coincide on the tensor product of two Köthe echelon or coechelon spaces. A major tool in the proof is the characterization of the επ-continuity of the tensor product of two diagonal operators from to . Several sharp forms of this result are also included.
Colacunary sequences in L-spaces
Combinatorial inequalities and subspaces of L₁
Let M₁ and M₂ be N-functions. We establish some combinatorial inequalities and show that the product spaces are uniformly isomorphic to subspaces of L₁ if M₁ and M₂ are “separated” by a function , 1 < r < 2.
Comments to Enflo's construction of Banach space without the approximation property
Common fixed point theorems for commuting -uniformly Lipschitzian mappings.
Commutative, radical amenable Banach algebras
There has been a considerable search for radical, amenable Banach algebras. Noncommutative examples were finally found by Volker Runde [R]; here we present the first commutative examples. Centrally placed within the construction, the reader may be pleased to notice a reprise of the undergraduate argument that shows that a normed space with totally bounded unit ball is finite-dimensional; we use the same idea (approximate the norm 1 vector x within distance η by a “good” vector ; then approximate...
Commutators in real interpolation with quasi-power parameters.
Commutators on
Let T be a bounded linear operator on with 1 ≤ q < ∞ and 1 < p < ∞. Then T is a commutator if and only if for all non-zero λ ∈ ℂ, the operator T - λI is not X-strictly singular.
Compacidad débil en espacios de funciones integrables-Bochner, y la propiedad de Radon-Nikodym.
Compacité et dualité en analyse linéaire
Compact diagonal linear operators on Banach spaces with unconditional bases.
Compact embeddings of Brézis-Wainger type.
Let Ω be a bounded domain in Rn and denote by idΩ the restriction operator from the Besov space Bpq1+n/p(Rn) into the generalized Lipschitz space Lip(1,-α)(Ω). We study the sequence of entropy numbers of this operator and prove that, up to logarithmic factors, it behaves asymptotically like ek(idΩ) ~ k-1/p if α > max (1 + 2/p + 1/q, 1/p). Our estimates improve previous results by Edmunds and Haroske.