Relations between different notions measuring proximity to ℓ₁ and distortability of a Banach space are studied. The main result states that a Banach space all of whose subspaces have Bourgain ℓ₁-index greater than , α < ω₁, contains either an arbitrarily distortable subspace or an -asymptotic subspace.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-sm190-2-4, author = {Anna Maria Pelczar}, title = {Note on distortion and Bourgain l1-index}, journal = {Studia Mathematica}, volume = {192}, year = {2009}, pages = {147-161}, zbl = {1167.46006}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-sm190-2-4} }
Anna Maria Pelczar. Note on distortion and Bourgain ℓ₁-index. Studia Mathematica, Tome 192 (2009) pp. 147-161. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-sm190-2-4/