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Amalgamated products and properly 3-realizable groups

M. Cardenas·F. F. Lasheras·A. Quintero·D. Repovš
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Abstract

In this paper, we show that the class of all properly 3-realizable groups is closed under amalgamated free products (and HNN-extensions) over finite groups. We recall that $G$ is said to be properly 3-realizable if there exists a compact 2-polyhedron $K$ with $\pi_1(K) \cong G$ and whose universal cover $\tilde{K}$ has the proper homotopy type of a 3-manifold (with boundary).

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M. Cardenas, F. F. Lasheras, A. Quintero, D. Repovš. 2006-09-11. Amalgamated products and properly 3-realizable groups. https://doi.org/10.1016/j.jpaa.2005.12.006

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