On barely $\alpha$-compact spaces and remote points in $\beta _ \alpha X_ X$
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- by Robert L. Blair, Lech T. Polkowski and Mary Anne Swardson PDF
- Proc. Amer. Math. Soc. 107 (1989), 1079-1085 Request permission
Abstract:
Let $X$ be a Tychonoff space. It was proved by Terada that if the cellularity of $X$ is not Ulam-measurable, then no point of $\upsilon X\backslash X$ is a remote point of $X$. In this paper we generalize this result by proving that if $X$ is barely $\alpha$-compact, then no point in ${\beta _\alpha }X\backslash X$ is an $\alpha$-exotic point of $X$. This implies, in particular, that if no cellular family in $X$ has a $\alpha$-measurable cardinality, then no point of ${\beta _\alpha }X\backslash X$ is a remote point of $X$; the Terada theorem then follows as a corollary when $\alpha = {\omega _1}$.References
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Additional Information
- © Copyright 1989 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 107 (1989), 1079-1085
- MSC: Primary 54D40; Secondary 54A25, 54D60, 54G05
- DOI: https://doi.org/10.1090/S0002-9939-1989-1019758-1
- MathSciNet review: 1019758