0 On properties of theories which preclude the existence of universal models
نویسنده
چکیده
In this paper we investigate some properties of first order theories which prevent them from having universal models under certain cardinal arithmetic assumptions. Our results give a new syntactical condition, oak property, which is a sufficient condition for a theory not to have universal models in cardinality λ when certain cardinal arithmetic assumptions implying the failure of GCH (and close to the failure of SCH) hold.
منابع مشابه
On properties of theories which preclude the existence of universal models
We introduce the oak property of first order theories, which is a syntactical condition that we show to be sufficient for a theory not to have universal models in cardinality λ when certain cardinal arithmetic assumptions about λ implying the failure of GCH (and close to the failure of SCH) hold. We give two examples of theories that have the oak property and show that none of these examples sa...
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تاریخ انتشار 2007