{ "id": "1507.02118", "version": "v1", "published": "2015-07-08T12:13:42.000Z", "updated": "2015-07-08T12:13:42.000Z", "title": "Uniqueness of Limit Models in Classes with Amalgamation", "authors": [ "Rami Grossberg", "Monica VanDieren", "Andres Villaveces" ], "categories": [ "math.LO" ], "abstract": "We prove: Main Theorem: Let $\\mathcal{K}$ be an abstract elementary class satisfying the joint embedding and the amalgamation properties with no maximal models of cardinality $\\mu$. Let $\\mu$ be a cardinal above the the L\\\"owenheim-Skolem number of the class. If $\\mathcal{K}$ is $\\mu$-Galois-stable, has no $\\mu$-Vaughtian Pairs, does not have long splitting chains, and satisfies locality of splitting, then any two $(\\mu,\\sigma_\\ell)$-limits over $M$, for $\\ell\\in\\{1,2\\}$, are isomorphic over $M$. This theorem extends results of Shelah from \\cite{Sh394}, \\cite{Sh576}, \\cite{Sh600}, Kolman and Shelah in \\cite{KoSh} and Shelah and Villaveces from \\cite{ShVi}. A preliminary version of our uniqueness theorem, which was circulated in 2006, was used by Grossberg and VanDieren to prove a case of Shelah's categoricity conjecture for tame abstract elementary classes in \\cite{GrVa2}. Preprints of this paper have also influenced the Ph.D. theses of Drueck \\cite{Dr} and Zambrano \\cite{Za}. This paper also serves the expository role of presenting together the arguments in \\cite{Va1} and \\cite{Va2} in a more natural context in which the amalgamation property holds and this work provides an approach to the uniqueness of limit models that does not rely on Ehrenfeucht-Mostowski constructions.", "revisions": [ { "version": "v1", "updated": "2015-07-08T12:13:42.000Z" } ], "analyses": { "keywords": [ "limit models", "tame abstract elementary classes", "shelahs categoricity conjecture", "amalgamation property holds", "theorem extends results" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2015arXiv150702118G" } } }