English

Accumulation Points of Graphs of Baire-1 and Baire-2 Functions

Classical Analysis and ODEs 2017-06-13 v3

Abstract

During the last few decades E. S. Thomas, S. J. Agronsky, J. G. Ceder, and T. L. Pearson gave an equivalent definition of the real Baire class 1 functions by characterizing their graph. In this paper, using their results, we consider the following problem: let TT be a given subset of [0,1]×R[0,1]\times\mathbb{R}. When can we find a function f:[0,1]Rf:[0,1]\rightarrow\mathbb{R} such that the accumulation points of its graph are exactly the points of TT? We show that if such a function exists, we can choose it to be a Baire-2 function. We characterize the accumulation sets of bounded and not necessarily bounded functions separately. We also examine the similar question in the case of Baire-1 functions.

Keywords

Cite

@article{arxiv.1512.00380,
  title  = {Accumulation Points of Graphs of Baire-1 and Baire-2 Functions},
  author = {Balázs Maga},
  journal= {arXiv preprint arXiv:1512.00380},
  year   = {2017}
}

Comments

Published in Real Analysis Exchange, Volume 41, Issue 2. Earlier available as "Accumulation Points of Graphs of Real Functions", apart from the title, the paper has not been modified