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arXiv · 2303.04246

Infinite-dimensional Ramsey theory for binary free amalgamation classes

Natasha Dobrinen·Andy Zucker
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Abstract

We develop infinite-dimensional Ramsey theory for Fraïssé limits of finitely constrained free amalgamation classes in finite binary languages. We show that our approach is optimal and in particular, recovers the exact big Ramsey degrees proved in [2] for these structures. A crucial step in the work develops the new notion of an A.3(2)-ideal and shows that Todorcevic's Abstract Ramsey Theorem holds when Axiom A.3(2) is replaced by the weaker assumption of an A.3(2)-ideal.

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Natasha Dobrinen, Andy Zucker. 2023-12-23. Infinite-dimensional Ramsey theory for binary free amalgamation classes. https://arxiv.org/abs/2303.04246

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