English

On Gibson functions with connected graphs

General Topology 2014-07-25 v1

Abstract

A function f:XYf:X\to Y between topological spaces is said to be a {\it weakly Gibson function} if f(G)f(G)f(\overline{G})\subseteq \overline{f(G)} for any open connected set \mbox{GXG\subseteq X}. We call a function f:XYf:X\to Y {\it segmentary connected} if XX is topological vector space and f([a,b])f([a,b]) is connected for every segment [a,b]X[a,b]\subseteq X. We show that if XX is a hereditarily Baire space, YY is a metric space, \mbox{f:XYf:X\to Y} is a Baire-one function and one of the following conditions holds: (i) XX is a connected and locally connected space and ff is a weakly Gibson function, (ii) XX is an arcwise connected space and ff is a Darboux function, (iii) XX is a topological vector space and ff is a segmentary connected function, then ff has a connected graph.

Keywords

Cite

@article{arxiv.1407.6515,
  title  = {On Gibson functions with connected graphs},
  author = {Olena Karlova and Volodymyr Mykhaylyuk},
  journal= {arXiv preprint arXiv:1407.6515},
  year   = {2014}
}
R2 v1 2026-06-22T05:12:01.958Z