Spaces in which the nondegenerate connected sets are the cofinite sets
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- by Gary Gruenhage
- Proc. Amer. Math. Soc. 122 (1994), 911-924
- DOI: https://doi.org/10.1090/S0002-9939-1994-1287102-2
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Abstract:
Assuming the continuum hypothesis (CH), we construct a perfectly normal space X such that $Y \subset X$ is connected and nondegenerate iff $X\backslash Y$ is finite. We also show that completely regular, as well as countable Hausdorff, examples of this kind can be obtained under axioms weaker than CH, e.g., Martin’s Axiom.References
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Bibliographic Information
- © Copyright 1994 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 122 (1994), 911-924
- MSC: Primary 54D05; Secondary 54A35, 54G20
- DOI: https://doi.org/10.1090/S0002-9939-1994-1287102-2
- MathSciNet review: 1287102