Subnormality in $PD_3$-groups and $L^2$-Betti numbers

J. A. Hillman

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arXiv · 2106.15750

Subnormality in $PD_3$-groups and $L^2$-Betti numbers

J. A. Hillman

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Abstract

We reconsider work of Elkalla on subnormal subgroups of 3-manifold groups, giving essentially algebraic arguments that extend to the case of $PD_3$-groups and group pairs. However the argument relies on an $L^2$-Betti number hypothesis which has not yet been shown to hold in general.

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BibTeX RIS

J. A. Hillman. 2023-07-20. Subnormality in $PD_3$-groups and $L^2$-Betti numbers. https://arxiv.org/abs/2106.15750

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