论文信息 - On potential isomorphism and non-structure

On potential isomorphism and non-structure

Abstract.We show in the paper that for any non-classifiable countable theory T there are non-isomorphic models and that can be forced to be isomorphic without adding subsets of small cardinality. By making suitable cardinal arithmetic assumptions we can often preserve stationary sets as well. We also study non-structure theorems relative to the Ehrenfeucht-Fraïssé game.

Tapani Hyttinen | Mika Rautila | Taneli Huuskonen

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