On the extension of Lipschitz-Hölder maps on spaces
On the interpolation of sublinear operators
On the range space of Yano's extrapolation theorem and new extrapolation estimates at infinity.
Given a sublinear operator T satisfying that ||Tf||Lp(ν) ≤ C/(p-1) ||f||Lp(μ), for every 1 < p ≤ p0, with C independent of f and p, it was proved in [C] that... [check the paper abstract for the formula]This estimate implies that T: L log L → B, where B is a rearrangement invariant space. The purpose of this note is to give several characterizations of the space B and study its associate space. This last information allows us to formulate an extrapolation result of Zygmund type for linear...
On the reitration property of ... spaces.
On the relation between complex and real methods of interpolation
We study those compatible couples of Banach spaces for which the complex method interpolation spaces are also described by the K-method of interpolation. As an application we present counter-examples to Cwikel's conjecture that all interpolation spaces of a Banach couple are described by the K-method whenever all complex interpolation spaces have this property.
On the structure of ultraproducts of real interpolation spaces.
Ondelettes, espaces d’interpolation et applications
Nous établissons des résultats d’interpolation non-standards entre les espaces de Besov et les espaces et , avec des applications aux lemmes de régularité en moyenne et aux inégalités de type Gagliardo-Nirenberg. La preuve de ces résultats utilise les décompositions dans des bases d’ondelettes.
Operator inequalities, geodesics and interpolation