The Turing Closure of an Archimedean Field
نویسندگان
چکیده
A BSS machine is δ-uniform if it does not use exact tests; such machines are equivalent (modulo parameters) to Type 2 Turing machines. We define a notion of closure related to Turing machines for archimedean fields, and show that such fields admit nontrivial δ-uniformly decidable sets iff they are not Turing closed. Then, the partially ordered set of Turing closed fields is proved isomorphic to the ideal completion of unsolvability degrees.
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ورودعنوان ژورنال:
- Theor. Comput. Sci.
دوره 231 شماره
صفحات -
تاریخ انتشار 1998