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arXiv · 2205.11674

On Countably $\alpha$-Compact Topological 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.

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BibTeXRIS

Eman Almuhur, Muhammad Ahsan Khan. 2022-05-23. On Countably $\alpha$-Compact Topological Spaces. https://arxiv.org/abs/2205.11674

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