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arXiv · 1801.06974

C*-superrigidity of 2-step nilpotent groups

Caleb Eckhardt·Sven Raum
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Abstract

We show that torsion-free finitely generated nilpotent groups are characterised by their group C*-algebras and we additionally recover their nilpotency class as well as the subquotients of the upper central series. We then use a C*-bundle decomposition and apply K-theoretic methods based on noncommutative tori to prove that every torsion-free finitely generated 2-step nilpotent group can be recovered from its group C*-algebra.

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Caleb Eckhardt, Sven Raum. 2018-01-22. C*-superrigidity of 2-step nilpotent groups. https://arxiv.org/abs/1801.06974

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