English

Complemented subspaces of spaces obtained by interpolation

Functional Analysis 2008-02-03 v2

Abstract

If Z is a quotient of a subspace of a separable Banach space X, and V is any separable Banach space, then there is a Banach couple (A_0,A_1) such that A_0 and A_1 are isometric to XVX\oplus V, and any intermediate space obtained using the real or complex interpolation method contains a complemented subspace isomorphic to Z. Thus many properties of Banach spaces, including having non-trivial cotype, having the Radon-Nikodym property, and having the analytic unconditional martingale difference sequence property, do not pass to intermediate spaces.

Keywords

Cite

@article{arxiv.math/9201212,
  title  = {Complemented subspaces of spaces obtained by interpolation},
  author = {D. J. H. Garling and Stephen J. Montgomery-Smith},
  journal= {arXiv preprint arXiv:math/9201212},
  year   = {2008}
}