Mutual definability does not imply definitional equivalence, a simple example

نویسندگان

  • Hajnal Andréka
  • Judit X. Madarász
  • István Németi
چکیده

We give two theories, Th1 and Th2, which are explicitly definable over each other (i.e. the relation symbols of one theory are explicitly definable in the other, and vice versa), but are not definitionally equivalent. The languages of the two theories are disjoint.

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عنوان ژورنال:
  • Math. Log. Q.

دوره 51  شماره 

صفحات  -

تاریخ انتشار 2005