English

On Countably $\alpha$-Compact Topological Spaces

General Topology 2022-05-25 v1 Functional Analysis

Abstract

In this paper, some features of countably α\alpha-compact topological spaces are presented and proven. The connection between countably α\alpha% -compact, Tychonoff, and α\alpha-Hausdorff spaces is explained. The space is countably α\alpha-compact space iff every locally finite family of non-empty subsets of such space is finite is demonstrated. The countably % \alpha-compact space with weight greater than or equal to 0\aleph_0 is the α\alpha-continuous image of a closed subspace of the cube D0D^{\aleph_0} is discussed. The boundedness of α\alpha-continuous functions mapping α\alpha% -compact spaces to other spaces is cleared. Moreover, the α\alpha% -continuous function mapping the space XX to the countably α\alpha-compact space YY is an α\alpha-closed subset of X×YX\times Y is argued and proved. We explained that the α\alpha-continuous functions mapping any topological space to a countably α\alpha-compact space can be extended over its domain under some constraints. We claimed that the property of being α\alpha% -compact is countably α\alpha-compact but the converse is not and the countable union of countably α\alpha-compact subspaces of XX is also countably α\alpha-compact.

Keywords

Cite

@article{arxiv.2205.11674,
  title  = {On Countably $\alpha$-Compact Topological Spaces},
  author = {Eman Almuhur and Muhammad Ahsan Khan},
  journal= {arXiv preprint arXiv:2205.11674},
  year   = {2022}
}
R2 v1 2026-06-24T11:26:21.249Z