Compact covering mappings and cofinal families of compact subsets of a Borel set
نویسندگان
چکیده
منابع مشابه
Compact Covering Mappings between Borel Sets and the Size of Constructible Reals
We prove that the topological statement: “Any compact covering mapping between two Borel sets is inductively perfect” is equivalent to the set-theoretical statement: “ ∀α ∈ ωω , א 1 < א1”. The starting point of this work is the following topological problem: Problem. Is any compact covering mapping between two Borel spaces inductively perfect? We recall that if f : X → Y is a continuous and ont...
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ژورنال
عنوان ژورنال: Fundamenta Mathematicae
سال: 2001
ISSN: 0016-2736,1730-6329
DOI: 10.4064/fm167-3-2