Kenilworth

Mátrai, Tamás

doi:10.1090/S0002-9939-08-09615-9

Kenilworth
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by Tamás Mátrai

Proc. Amer. Math. Soc. 137 (2009), 1115-1125

DOI: https://doi.org/10.1090/S0002-9939-08-09615-9

Published electronically: October 23, 2008

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Abstract:

We construct a $G_{\delta }$ $\sigma$-ideal $\mathcal {I}$ of compact subsets of $2^{\omega }$ such that $\mathcal {I}$ contains all the singletons but there is no dense $G_{\delta }$ set $D \subseteq 2^{\omega }$ such that $\{K \subseteq D \colon K\textrm { compact}\} \subseteq \mathcal {I}$. This answers a question of A. S. Kechris in the negative.

References

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