English

Banach spaces without minimal subspaces

Functional Analysis 2011-04-19 v2 Logic

Abstract

We prove three new dichotomies for Banach spaces \`a la W.T. Gowers' dichotomies. The three dichotomies characterise respectively the spaces having no minimal subspaces, having no subsequentially minimal basic sequences, and having no subspaces crudely finitely representable in all of their subspaces. We subsequently use these results to make progress on Gowers' program of classifying Banach spaces by finding characteristic spaces present in every space. Also, the results are used to embed any partial order of size 1\aleph_1 into the subspaces of any space without a minimal subspace ordered by isomorphic embeddability.

Keywords

Cite

@article{arxiv.0711.1350,
  title  = {Banach spaces without minimal subspaces},
  author = {Valentin Ferenczi and Christian Rosendal},
  journal= {arXiv preprint arXiv:0711.1350},
  year   = {2011}
}
R2 v1 2026-06-21T09:41:29.082Z