A closed separable subspace of $\beta \textbf {N}$ which is not a retract
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- by Petr Simon PDF
- Trans. Amer. Math. Soc. 299 (1987), 641-655 Request permission
Abstract:
We shall exhibit a countable subset, $X$, of ${{\mathbf {N}}^{\ast }}$ whose closure is not a retract of $\beta {\mathbf {N}}$. The points of $X$ are constructed in $c$ steps with the aid of an independent matrix of subsets of $\omega$.References
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Additional Information
- © Copyright 1987 American Mathematical Society
- Journal: Trans. Amer. Math. Soc. 299 (1987), 641-655
- MSC: Primary 54G20; Secondary 04A20, 54D35
- DOI: https://doi.org/10.1090/S0002-9947-1987-0869226-5
- MathSciNet review: 869226