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arXiv · 1403.5763

Indiscernible extraction and Morley sequences

Sebastien Vasey
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Abstract

We present a new proof of the existence of Morley sequences in simple theories. We avoid using the Erd\H{o}s-Rado theorem and instead use only Ramsey's theorem and compactness. The proof shows that the basic theory of forking in simple theories can be developed using only principles from "ordinary mathematics", answering a question of Grossberg, Iovino and Lessmann, as well as a question of Baldwin.

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Sebastien Vasey. 2014-03-23. Indiscernible extraction and Morley sequences. https://doi.org/10.1215/00294527-3800865

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