Isomorphism of Homogeneous Structures
نویسندگان
چکیده
منابع مشابه
Isomorphism of Homogeneous Structures
We consider the complexity of the isomorphism relation on countable first-order structures with transitive automorphism groups. We use the theory of Borel reducibility of equivalence relations to show that the isomorphism problem for vertex-transitive graphs is as complicated as the isomorphism problem for arbitrary graphs, and determine for which first-order languages the isomorphism problem f...
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A relational first order structure is homogeneous if every isomorphism between finite substructures extends to an automorphism. Familiar examples of such structures include the rational numbers with the usual order relation, the countable random and so called Rado graph, and many others. Countable homogeneous structures arise as Fraı̈ssé limits of amalgamation classes of finite structures, and h...
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ژورنال
عنوان ژورنال: Notre Dame Journal of Formal Logic
سال: 2009
ISSN: 0029-4527
DOI: 10.1215/00294527-2008-024