Determining Whether V(A) Has a Model Companion is Undecidable
نویسنده
چکیده
Using techniques pioneered by R. McKenzie, we prove that there is no algorithm which, given a finite algebra in a finite language, determines whether the variety (equational class) generated by the algebra has a model companion. In particular, there exists a finite algebra such that the variety it generates has no model companion; this answers a question of Burris and Werner from 1979.
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عنوان ژورنال:
- IJAC
دوره 14 شماره
صفحات -
تاریخ انتشار 2004