A rigid Borel space
نویسندگان
چکیده
منابع مشابه
A Space with Only Borel Subsets
Miklós Laczkovich (Budapest) asked if there exists a Haussdorff (or even normal) space in which every subset is Borel yet it is not meager. The motivation of the last condition is that under MAκ every subspace of the reals of cardinality κ has the property that all subsets are Fσ however Martin’s axiom also implies that these subsets are meager. Here we answer Laczkovich’ question. I thank Pete...
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 1991
ISSN: 0002-9939
DOI: 10.1090/s0002-9939-1991-1076571-6