Borel hierarchies in infinite products of Polish spaces
نویسندگان
چکیده
منابع مشابه
Borel hierarchies in infinite products of Polish spaces
Let H be a product of countably infinite number of copies of an uncountable Polish space X . Let Σξ (Σξ ) be the class of Borel sets of additive class ξ for the product of copies of the discrete topology on X (the Polish topology on X), and let B = ∪ξ<ω1Σξ . We prove in the Lévy–Solovay model that Σξ = Σξ ∩B
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ژورنال
عنوان ژورنال: Proceedings Mathematical Sciences
سال: 2007
ISSN: 0253-4142,0973-7685
DOI: 10.1007/s12044-007-0016-y