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arXiv · 1501.06682

The $Σ$-invariants of Thompson's group $F$ via Morse theory

Stefan Witzel·Matthew C. B. Zaremsky
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Abstract

Bieri, Geoghegan and Kochloukova computed the BNSR-invariants $Σ^m(F)$ of Thompson's group $F$ for all $m$. We recompute these using entirely geometric techniques, making use of the Stein--Farley CAT(0) cube complex on which $F$ acts.

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Stefan Witzel, Matthew C. B. Zaremsky. 2015-04-28. The $Σ$-invariants of Thompson's group $F$ via Morse theory. https://arxiv.org/abs/1501.06682

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