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arXiv · 2609.37562

Every countable group embeds in a group of type $\mathrm{FP}_n$

Laurent Bartholdi·Roman Mikhailov
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Abstract

For every integer $n\ge2$, we prove that every countable group embeds in a group of type $\mathrm{FP}_n$. We also construct a group of type $\mathrm{F}_n$ containing a copy of every recursively presented group. Consequently, a finitely generated group embeds in a group of type $\mathrm{F}_n$ if and only if it is recursively presented. This answers questions of Fournier-Facio and Zaremsky, and confirms a suggestion of Gromov.

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Laurent Bartholdi, Roman Mikhailov. 2026-09-29. Every countable group embeds in a group of type $\mathrm{FP}_n$. https://arxiv.org/abs/2609.37562

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