The Theory of the Α Degrees Is Undecidable
نویسندگان
چکیده
Let α be an arbitrary Σ1-admissible ordinal. For each n, there is a formula φn(~x, ~y) such that for any relation R on a finite set F with n elements, there are α-degrees ~ p such that the relation defined by φn(~x, ~ p) is isomorphic to R. Consequently, the theory of α-degrees
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تاریخ انتشار 2008