Borel classes of uniformizations of sets with large sections
نویسندگان
چکیده
منابع مشابه
Borel Classes of Uniformizations of Sets with Large Sections
We give several refinements of known theorems on Borel uniformizations of sets with ”large sections”. In particular, we show that a set B ⊂ [0, 1] × [0, 1] which belongs to Σ0α, α ≥ 2, and which has all ”vertical” sections of positive Lebesgue measure, has a Π0α uniformization which is the graph of a Σ0α-measurable mapping. We get a similar result for sets with nonmeager sections. As a corollar...
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ژورنال
عنوان ژورنال: Fundamenta Mathematicae
سال: 2010
ISSN: 0016-2736,1730-6329
DOI: 10.4064/fm207-2-3