Two examples of Borel partially ordered sets with the countable chain condition
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- by Stevo Todorčević PDF
- Proc. Amer. Math. Soc. 112 (1991), 1125-1128 Request permission
Abstract:
We define an open symmetric two-place relation on the reals such that the reals cannot be covered by countably many sets of related elements, but there is no uncountable set of unrelated elements. The poset $\mathcal {P}$ of finite sets of related elements satisfies the countable chain condition but it may fail to have the property K, i.e., a substantial irregularity can be injected in $\mathcal {P}$.References
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Additional Information
- © Copyright 1991 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 112 (1991), 1125-1128
- MSC: Primary 03E05; Secondary 03E15, 54H05
- DOI: https://doi.org/10.1090/S0002-9939-1991-1069693-7
- MathSciNet review: 1069693