Bounded query classes and the difference hierarchy
نویسندگان
چکیده
Let A be any nonrecursive set. We deene a hierarchy of sets (and a corresponding hierarchy of degrees) that are reducible to A based on bounding the number of queries to A that an oracle machine can make. When A is the halting problem K our hierarchy of sets interleaves with the diierence hierarchy 1 on the r.e. sets in a logarithmic way; this follows from a tradeoo between the number of parallel queries and the number of serial queries needed to compute a function with oracle K.
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عنوان ژورنال:
- Arch. Math. Log.
دوره 29 شماره
صفحات -
تاریخ انتشار 1989