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arXiv · 2606.27408

The Baumslag-Gersten group and a problem of Olshanskii

Carl-Fredrik Nyberg-Brodda
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Abstract

We prove that a certain representation of the Baumslag-Gersten one-relator group $\mathrm{BG}(1,2)$ by germs of continuous functions is not faithful. This gives a negative answer to a problem of A. Yu. Olshanskii from 2010 (Problem 17.99 in the Kourovka Notebook).

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Carl-Fredrik Nyberg-Brodda. 2026-06-25. The Baumslag-Gersten group and a problem of Olshanskii. https://arxiv.org/abs/2606.27408

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