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The relation of recursive isomorphism for countable structures

  • Riccardo Camerlo (a1)


It is shown that the relations of recursive isomorphism on countable trees, groups, Boolean algebras, fields and total orderings are universal countable Borel equivalence relations, thus providing a countable analogue of the Borel completeness of the isomorphism relations on these same classes.


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Dipartimento di matematica, Università degli studi di Torino, Via Carlo Alberto 10, 10123 Torino, Italy, E-mail:


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The relation of recursive isomorphism for countable structures

  • Riccardo Camerlo (a1)


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