Non-Maximal Decidable Structures
نویسندگان
چکیده
Given any infinite structureM with a decidable first-order theory, we give a sufficient condition in terms of the Gaifman graph of M, which ensures that M can be expanded with some non-definable predicate in such a way that the first-order theory of the expansion is still decidable. LACL Technical Report 2007-06
منابع مشابه
Weakly maximal decidable structures
We prove that there exists a structure M whose monadic second order theory is decidable, and such that the elementary theory of every expansion of M by a constant is undecidable. 1991 Mathematics Subject Classification. 03B25, 03C57, 03D05.
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