A Z–structure on a group G, defined by M Bestvina, is a pair (X̂,Z) of spaces such that X̂ is a compact ER, Z is a Z–set in X̂, G acts properly and cocompactly on X = X̂∖Z and the collection of translates of any compact set in X forms a null sequence in X̂. It is natural to ask whether a given group admits a Z–structure. In this paper, we show that if two groups each admit a Z–structure, then so do their free and direct products.
Keywords: $\mathcal{Z}$–structure, boundary, free product, direct product, product group
Tirel, Carrie J  1
@article{10_2140_agt_2011_11_2587,
author = {Tirel, Carrie~J},
title = {\ensuremath{\mathscr{Z}}{\textendash}Structures on product groups},
journal = {Algebraic and Geometric Topology},
pages = {2587--2625},
year = {2011},
volume = {11},
number = {5},
doi = {10.2140/agt.2011.11.2587},
url = {http://geodesic.mathdoc.fr/articles/10.2140/agt.2011.11.2587/}
}
Tirel, Carrie J. 𝒵–Structures on product groups. Algebraic and Geometric Topology, Tome 11 (2011) no. 5, pp. 2587-2625. doi: 10.2140/agt.2011.11.2587
[1] , Local homology properties of boundaries of groups, Michigan Math. J. 43 (1996) 123
[2] , , The boundary of negatively curved groups, J. Amer. Math. Soc. 4 (1991) 469
[3] , , Metric spaces of non-positive curvature, Grund. der Math. Wissenschaften 319, Springer (1999)
[4] , On Bestvina–Mess formula, from: "Topological and asymptotic aspects of group theory" (editors R Grigorchuk, M Mihalik, M Sapir, Z Šunik), Contemp. Math. 394, Amer. Math. Soc. (2006) 77
[5] , Dimension theory, North-Holland Math. Library 19, North-Holland (1978)
[6] , , EZ–structures and topological applications, Comment. Math. Helv. 80 (2005) 103
[7] , Some theorems on absolute neighborhood retracts, Ark. Mat. 1 (1951) 389
[8] , Theory of retracts, Wayne State Univ. Press (1965) 234
[9] , , Boundaries of systolic groups, Geom. Topol. 13 (2009) 2807
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