Abstract
We investigate the Reidemeister spectrum of direct products of nilpotent groups. More specifically, we prove that the Reidemeister spectra of the individual factors yield complete information for the Reidemeister spectrum of the direct product if all groups are finitely generated torsion-free nilpotent and have a directly indecomposable rational Malcev completion. We show this by determining the complete automorphism group of the direct product.
Funding source: Fonds Wetenschappelijk Onderzoek
Award Identifier / Grant number: 1112522N
Funding statement: The author is funded by an FWO-fellowship fundamental research (file number 1112522N).
Acknowledgements
The author thanks Karel Dekimpe and the anonymous referee for their useful remarks and suggestions, and Thomas Witdouck and Maarten Lathouwers for the helpful discussions.
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Communicated by: Rachel Skipper
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