2019/03/14 by Chloé Perin, Perin, Chloé
Computer Science · Mathematics · #Advanced Operator Algebra Research #FOS: Mathematics #Geometric and Algebraic Topology #Group Theory (math.GR) #Logic (math.LO) #semigroups and automata theory
paper · pdf · doi:10.48550/arxiv.1903.05876
openalex publication_date 2019/03/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In this note we give a new proof of the fact that an elementary subgroup (in the sense of first-order theory) of a non abelian free group \mathbbF must be a free factor. The proof is based on definability of orbits of elements of under automorphisms of \mathbbF fixing a large enough subset of \mathbbF.