A universal Lipschitz extension property of Gromov hyperbolic spaces.
A universal modulus for normed spaces
We define a handy new modulus for normed spaces. More precisely, given any normed space X, we define in a canonical way a function ξ:[0,1)→ ℝ which depends only on the two-dimensional subspaces of X. We show that this function is strictly increasing and convex, and that its behaviour is intimately connected with the geometry of X. In particular, ξ tells us whether or not X is uniformly smooth, uniformly convex, uniformly non-square or an inner product space.
A universal non-compact operator
A Universal Topology for Sequence Spaces.
A weakly pseudocompact subspace of Banach space is weakly compact
A₁-regularity and boundedness of Calderón-Zygmund operators
The Coifman-Fefferman inequality implies quite easily that a Calderón-Zygmund operator T acts boundedly in a Banach lattice X on ℝⁿ if the Hardy-Littlewood maximal operator M is bounded in both X and X'. We establish a converse result under the assumption that X has the Fatou property and X is p-convex and q-concave with some 1 < p, q < ∞: if a linear operator T is bounded in X and T is nondegenerate in a certain sense (for example, if T is a Riesz transform) then M is bounded in both X and...
About an example of a Banach space not weaky K-analytic.
About certain isomorphic properties of Banach spaces in projective tensor products.
This note is an announcement of results contained in the papers [4], [5], [6] concerning isomorphic properties of Banach spaces in projective tensor products (for this definition and some property we refer to [1]). At the end, some new result is obtained too.
About interpolation of subspaces of rearrangement invariant spaces generated by Rademacher system.
About some parameters of normed linear spaces
Si prendono in considerazione particolari costanti relative alla struttura della sfera unitaria di uno spazio di Banach. Se ne studiano alcune generali proprietà, con particolare riferimento alle relazioni con il modulo di convessità dello spazio. Se ne fornisce inoltre una esatta valutazione negli spazi .
About the Banach envelope of l1,∞.
About the class of ordered limited operators
We give a brief survey of recent results of order limited operators related to some properties on Banach lattices.
Absolutely (∞,p) summing and weakly-p-compact operators in Banach spaces.
A sequence (xn) in a Banach space X is said to be weakly-p-summable, 1 ≤ p < ∞, when for each x* ∈ X*, (x*xn) ∈ lp. We shall say that a sequence (xn) is weakly-p-convergent if for some x ∈ X, (xn - x) is weakly-p-summable.
Absolutely (∞,p) summing and weakly-p-compact operators in C(K).
In this note we review some results about:1. Representation of Absolutely (∞,p) summing operators (∏∞,p) in C(K,E)2. Dunford-Pettis properties.
Absolutely p-summing operators and Banach spaces containing all uniformly complemented
Absolutely P-Summing, P-Nuclear Operators and Their Conjugates.
Absolutely summing operators in -spaces and their applications
Abstract characterization of Orlicz-Kantorovich lattices associated with an -valued measure
An abstract characterization of Orlicz-Kantorovich lattices constructed by a measure with values in the ring of measurable functions is presented.
Abstract multiplication semigroups.
Acción dual de las copias, isométricas asintóticamente, de lp (1 ≤ p < ∞) y c0.