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The nilpotent genus of finitely generated residually nilpotent groups

  • Niamh O’Sullivan EMAIL logo
Published/Copyright: June 29, 2023

Abstract

Let 𝐺 and 𝐻 be residually nilpotent groups. Then 𝐺 and 𝐻 are in the same nilpotent genus if they have the same lower central quotients (up to isomorphism). A potentially stronger condition is that 𝐻 is para-𝐺 if there exists a monomorphism of 𝐺 into 𝐻 which induces isomorphisms between the corresponding quotients of their lower central series. We first consider finitely generated residually nilpotent groups and find sufficient conditions on the monomorphism so that 𝐻 is para-𝐺. We then prove that, for certain polycyclic groups, if 𝐻 is para-𝐺, then 𝐺 and 𝐻 have the same Hirsch length. We also prove that the pro-nilpotent completions of these polycyclic groups are locally polycyclic.

Acknowledgements

I would like to thank the anonymous referee for helpful comments and suggestions.

  1. Communicated by: Benjamin Klopsch

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Received: 2022-06-01
Revised: 2023-06-09
Published Online: 2023-06-29
Published in Print: 2024-01-01

© 2023 Walter de Gruyter GmbH, Berlin/Boston

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