English

Complemented copies of $\ell^1$ and Pelczynski's property (V*) in Bochner function spaces

Functional Analysis 2016-09-06 v1

Abstract

Let XX be a Banach space and (fn)n(f_n)_n be a bounded sequence in L1(X)L^1(X). We prove a complemented version of the celebrated Talagrand's dichotomy i.e we show that if (en)n(e_n)_n denotes the unit vector basis of c0c_0, there exists a sequence gnconv(fn,fn+1,)g_n \in \text{conv}(f_n,f_{n+1},\dots) such that for almost every ω\omega, either the sequence (gn(ω)en)(g_n(\omega) \otimes e_n) is weakly Cauchy in X^πc0X \widehat{\otimes}_\pi c_0 or it is equivalent to the unit vector basis of 1\ell^1. We then get a criterion for a bounded sequence to contain a subsequence equivalent to a complemented copy of 1\ell^1 in L1(X)L^1(X). As an application, we show that for a Banach space XX, the space L1(X)L^1(X) has Pe\l czy\'nski's property (V)(V^*) if and only if XX does.

Keywords

Cite

@article{arxiv.math/9410204,
  title  = {Complemented copies of $\ell^1$ and Pelczynski's property (V*) in Bochner function spaces},
  author = {Narcisse Randrianantoanina},
  journal= {arXiv preprint arXiv:math/9410204},
  year   = {2016}
}