English

Ideal convergent subsequences and rearrangements for divergent sequences of functions

Classical Analysis and ODEs 2016-04-30 v1 Functional Analysis

Abstract

Let \I\I be an ideal on N\N which is either analytic or coanalytic. Assume that (fn)(f_n) is a sequence of functions with the Baire property from a Polish space XX into a complete metric space ZZ, which is divergent on a comeager set. We investigate the Baire category of \I\I-convergent subsequences and rearrangements of (fn)(f_n). Our result generalizes a theorem of Kallman. A similar theorem for subsequences is obtained if (X,μ)(X,\mu) is a σ\sigma-finite complete measure space and a sequence (fn)(f_n) of measurable functions from XX to ZZ is \I\I-divergent μ\mu-almost everywhere. Then the set of subsequences of (fn)(f_n), \I\I-divergent μ\mu-almost everywhere, is of full product measure on {0,1}N\{ 0,1\}^\N. Here we assume additionally that I\mathcal I has property (G).

Keywords

Cite

@article{arxiv.1604.08359,
  title  = {Ideal convergent subsequences and rearrangements for divergent sequences of functions},
  author = {Marek Balcerzak and Michał Popławski and Artur Wachowicz},
  journal= {arXiv preprint arXiv:1604.08359},
  year   = {2016}
}