A countable dense homogeneous set of reals of size \aleph1
نویسندگان
چکیده
منابع مشابه
A countable dense homogeneous set of reals of size א
We prove there is a countable dense homogeneous subspace of R of size א1. The proof involves an absoluteness argument using an extension of the Lω1ω(Q) logic obtained by adding predicates for Borel sets. A separable topological space X is countable dense homogeneous (CDH) if, given any two countable dense subsets D and D′ of X, there is a homeomorphism h of X such that h[D] = D′. The main purpo...
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ژورنال
عنوان ژورنال: Fundamenta Mathematicae
سال: 2005
ISSN: 0016-2736,1730-6329
DOI: 10.4064/fm186-1-5