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arXiv · 2309.12213

The Sigma invariants for the Golden Mean Thompson group

Lewis Molyneux·Brita Nucinkis·Yuri Santos Rego
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Abstract

We use a method of Bieri, Geoghegan and Kochloukova to calculate the BNSR-invariants for the irrational slope Thompson's group $F_{\tau}$. To do so we establish conditions under which the Sigma invariants coincide with those of a subgroup of finite index, addressing a problem posed by Strebel.

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Lewis Molyneux, Brita Nucinkis, Yuri Santos Rego. 2023-09-21. The Sigma invariants for the Golden Mean Thompson group. https://arxiv.org/abs/2309.12213

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