English

Note on distortion and Bourgain $\ell_1$ index

Functional Analysis 2008-03-14 v2

Abstract

The relation between different notions measuring proximity to 1\ell_1 and distortability of a Banach space is studied. The main result states that a Banach space, whose all subspaces have Bourgain 1\ell_1 index greater than ωα\omega^\alpha, α<ω1\alpha<\omega_1, contains either an arbitrary distortable subspace or an 1α\ell_1^\alpha-asymptotic subspace.

Keywords

Cite

@article{arxiv.0709.2272,
  title  = {Note on distortion and Bourgain $\ell_1$ index},
  author = {Anna Maria Pelczar},
  journal= {arXiv preprint arXiv:0709.2272},
  year   = {2008}
}

Comments

14 pages, remarks and references added

R2 v1 2026-06-21T09:17:34.722Z