FINITARY REDUCIBILITY ON EQUIVALENCE RELATIONS
نویسندگان
چکیده
منابع مشابه
Finitary Reducibility on Equivalence Relations
We introduce the notion of finitary computable reducibility on equivalence relations on the domain ω. This is a weakening of the usual notion of computable reducibility, and we show it to be distinct in several ways. In particular, whereas no equivalence relation can be Π n+2-complete under computable reducibility, we show that, for every n, there does exist a natural equivalence relation which...
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Let E ⊆ F and E′ ⊆ F ′ be Borel equivalence relations on the standard Borel spaces X and Y , respectively. The pair (E,F ) is simultaneously Borel reducible to the pair (E′, F ′) if there is a Borel function f : X → Y that is both a reduction from E to E′ and a reduction from F to F ′. Simultaneous Borel embeddings and isomorphisms are defined analogously. We classify all pairs E ⊆ F of smooth ...
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ژورنال
عنوان ژورنال: The Journal of Symbolic Logic
سال: 2016
ISSN: 0022-4812,1943-5886
DOI: 10.1017/jsl.2016.23