ArticleOriginal scientific text
Title
Category theorems concerning Z-density continuous functions
Authors 1, 2
Affiliations
- Department of Mathematics, West Virginia University, Morgantown, West Virginia 26506, U.S.A.
- Department of Mathematics, University of Louisville, Louisville, Kentucky 40292, U.S.A.
Abstract
The ℑ-density topology on ℝ is a refinement of the natural topology. It is a category analogue of the density topology [9, 10]. This paper is concerned with ℑ-density continuous functions, i.e., the real functions that are continuous when the ℑ-density} topology is used on the domain and the range. It is shown that the family of ordinary continuous functions f: [0,1]→ℝ which have at least one point of ℑ-density continuity is a first category subset of C([0,1])= {f: [0,1]→ℝ: f is continuous} equipped with the uniform norm. It is also proved that the class of ℑ-density continuous functions, equipped with the topology of uniform convergence, is of first category in itself. These results remain true when the ℑ-density topology is replaced by the deep ℑ-density topology.
Keywords
ℑ-density topology, ℑ-density continuous functions, first category sets
Bibliography
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Additional information
http://matwbn.icm.edu.pl/ksiazki/fm/fm140/fm14017.pdf