Semilattices and Ramsey Property
نویسنده
چکیده
We consider S, the class of nite semilattices; T , the class of nite treeable semilattices; and Tm, the subclass of T which contains trees with branching bounded by m. We prove that ES, the class of nite lattices with linear extensions, is a Ramsey class. We calculate Ramsey degrees for structures in S, T and Tm. In addition to this we give a topological interpretation of our results and we apply our result to canonization of linear orderings on nite semilattices. In particular, we give rst two examples of a Fraïssé class K which is not a Hrushovski class, and automorphism group of the Fraïssé limit of K is non trivial and it is uniquely ergodic.
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تاریخ انتشار 2013