Mass problems and measure-theoretic regularity
نویسنده
چکیده
A well known fact is that every Lebesgue measurable set is regular, i.e., it includes an Fσ set of the same measure. We analyze this fact from a metamathematical or foundational standpoint. We study a family of Muchnik degrees corresponding to measure-theoretic regularity at all levels of the effective Borel hierarchy. We prove some new results concerning Nies’s notion of LR-reducibility. We build some ω-models of RCA0 which are relevant for the reverse mathematics of measure-theoretic regularity.
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عنوان ژورنال:
- Bulletin of Symbolic Logic
دوره 15 شماره
صفحات -
تاریخ انتشار 2009