On Infinitary Rational Relations and Borel Sets
نویسنده
چکیده
We prove in this paper that there exists some infinitary rational relations which are Σ03-complete Borel sets and some others which are Π03-complete. These results give additional answers to questions of Simonnet [Sim92] and of Lescow and Thomas [Tho90] [LT94].
منابع مشابه
Topological and Arithmetical Properties of Infinitary Rational Relations
We prove that there exist some infinitary rational relations which are analytic but non Borel sets, giving an answer to a question of Simonnet [Sim92]. Then we show that for every countable ordinal α one cannot decide whether a given infinitary rational relation is in the Borel class Σα ( respectively Π 0 α). Furthermore one cannot decide whether a given infinitary rational relation is a Borel ...
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We prove in this paper that there exists some infinitary rational relations which are analytic but non Borel sets, giving an answer to a question of Simonnet [Sim92]. 1991 Mathematics Subject Classification. 68Q45; 03D05; 03D55; 03E15.
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