On rearrangement invariant and majorant hulls of averages of rearrangement invariant and majorant ideals

Subspaces of Rearrangement-invariant Spaces

We prove a number of results concerning the embedding of a Banach lattice X into an r. i. space Y. For example we show that if Y is an r. i. space on [0, oo) which is/7-convex for some/? > 2 and has nontrivial concavity then any Banach lattice X which is r-convex for some r > 2 and embeds into Y must embed as a sublattice. Similar conclusions can be drawn under a variety of hypotheses on Y; if ...

The Level Function in Rearrangement Invariant Spaces

An exact expression for the down norm is given in terms of the level function on all rearrangement invariant spaces and a useful approximate expression is given for the down norm on all rearrangement invariant spaces whose upper Boyd index is not one.

Discretization and Anti-discretization of Rearrangement-invariant Norms

Abstract We develop a new method of discretization and anti-discretization of weighted inequalities which we apply to norms in classical Lorentz spaces and to spaces endowed with the so-called Hilbert norm. Main applications of our results include new integral conditions characterizing embeddings Γp(v) ↪→ Γq(w) and Γp(v) ↪→ Λq(w) and an integral characterization of the associate space to Γp(v),...

On the Hardy - Littlewood majorant

The Natural Rearrangement Invariant Structure on Tensor Products

We prove that the only rearrangement invariant (r.i.) spaces for which there exists a crossnorm verifying that the tensor product of these spaces preserves the “natural” r.i. space structure, in the sense that it makes the multiplication operator B a topological isomorphism, are the Lp spaces.