English

Operators in tight by support Banach spaces

Functional Analysis 2016-02-15 v2

Abstract

We answer the question of W.T. Gowers, giving an example of a bounded operator on a subspace of Gowers unconditional space which is not a strictly singular perturbation of a restriction of a diagonal operator. We make some observations on operators in arbitrary tight by support Banach space, showing in particular that in such space no two isomorphic infinitely dimensional subspaces form a direct sum.

Keywords

Cite

@article{arxiv.1504.02701,
  title  = {Operators in tight by support Banach spaces},
  author = {Antonis Manoussakis and Anna Pelczar-Barwacz},
  journal= {arXiv preprint arXiv:1504.02701},
  year   = {2016}
}

Comments

17 pages. Revised version - added Remark 1.2, Theorem 2.10 and corresponding changes in the paper

R2 v1 2026-06-22T09:14:12.134Z