English

Games characterizing limsup functions and Baire class 1 functions

General Topology 2020-10-08 v1

Abstract

We consider a real-valued function ff defined on the set of infinite branches XX of a countably branching pruned tree TT. The function ff is said to be a \textit{limsup function} if there is a function u ⁣:TRu \colon T \to \mathbb{R} such that f(x)=lim suptu(x0,,xt)f(x) = \limsup_{t \to \infty} u(x_{0},\dots,x_{t}) for each xXx \in X. We study a game characterization of limsup functions, as well as a novel game characterization of functions of Baire class 1.

Keywords

Cite

@article{arxiv.2010.03327,
  title  = {Games characterizing limsup functions and Baire class 1 functions},
  author = {Márton Elekes and János Flesch and Viktor Kiss and Donát Nagy and Márk Poór and Arkadi Predtetchinski},
  journal= {arXiv preprint arXiv:2010.03327},
  year   = {2020}
}
R2 v1 2026-06-23T19:07:31.349Z