Turing degrees of hypersimple relations on computable structures
نویسنده
چکیده
Let A be an infinite computable structure, and let R be an additional computable relation on its domain A. The syntactic notion of formal hypersimplicity of R on A, first introduced and studied by G. Hird, is analogous to the computability-theoretic notion of hypersimplicity of R on A, given the definability of certain effective sequences of relations on A. Assuming that R is formally hypersimple on A, we give general sufficient conditions for the existence of a computable isomorphic copy of A on whose domain the image of R is hypersimple and of arbitrary nonzero computably enumerable Turing degree. AMS Classification: 03C57, 03D45
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عنوان ژورنال:
- Ann. Pure Appl. Logic
دوره 121 شماره
صفحات -
تاریخ انتشار 2003