On Countably $\alpha$-Compact Topological Spaces

TL;DR

This paper explores properties of countably lpha-compact topological spaces, their relationships with other classes, and the behavior of lpha-continuous functions, providing new characterizations and extension results.

Contribution

It introduces new characterizations of countably lpha-compact spaces, examines their relationship with lpha-Hausdorff and Tychonoff spaces, and studies properties of lpha-continuous functions.

Findings

Countably lpha-compact spaces are characterized by finite locally finite families.

Such spaces are lpha-continuous images of closed subspaces of the cube D^{\u001alpha_0}.

lpha-continuous functions from these spaces are lpha-closed subsets of product spaces.

Abstract

In this paper, some features of countably $\alpha$-compact topological spaces are presented and proven. The connection between countably $\alpha$% -compact, Tychonoff, and $\alpha$-Hausdorff spaces is explained. The space is countably $\alpha$-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 $\aleph_0$ is the $\alpha$-continuous image of a closed subspace of the cube $D^{\aleph_0}$ is discussed. The boundedness of $\alpha$-continuous functions mapping $\alpha$% -compact spaces to other spaces is cleared. Moreover, the $\alpha$% -continuous function mapping the space $X$ to the countably $\alpha$-compact space $Y$ is an $\alpha$-closed subset of $X\times Y$ is argued and proved. We explained that the $\alpha$-continuous functions mapping any topological space to a countably $\alpha$-compact space can be extended over its domain under some constraints. We claimed that the property of being $\alpha$% -compact is countably $\alpha$-compact but the converse is not and the countable union of countably $\alpha$-compact subspaces of $X$ is also countably $\alpha$-compact.