Automorphisms of the Rado meet-tree

2023/10/11 by Itay Kaplan, Kaplan, Itay, Binyamin Riahi +3 · 1 citation
Computer Science · Mathematics · #03C15 #03C98 #20B27 #Advanced Graph Theory Research #Advanced Topology and Set Theory #FOS: Mathematics #Group Theory (math.GR) #Logic (math.LO) #semigroups and automata theory

paper · pdf · doi:10.48550/arxiv.2310.07614

openalex publication_date 2023/10/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We prove that the group of automorphisms of the generic meet-tree expansion of an infinite non-unary free Fra"ıssé limit over a finite relational language is simple. As a prototypical case, the group of automorphism of the Rado meet-tree (i.e. the Fra"ıssé limit of finite graphs which are also meet-trees) is simple.

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• Extensive embeddings into Fraïssé structures and stationary weak independence relations

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