On properly 3-realizable groups
نویسندگان
چکیده
منابع مشابه
Amalgamated Products and Properly 3-realizable Groups
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 π1(K) = G and whose universal cover K̃ has the proper homotopy type of a 3-manifold (with boundary).
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The most useful constructions in Combinatorial Group Theory are amalgamated free products and HNN-extensions, and they are the two basic examples in the theory of graphs of groups due to Bass and Serre (see [9]). We recall that given a group G and a subgroup H 6 G together with monomorphisms (respectively homomorphisms) ψ, φ : H −→ G, the group determined by the presentation 〈 G, t; t−1ψ(h)t = ...
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ژورنال
عنوان ژورنال: Topology and its Applications
سال: 2005
ISSN: 0166-8641
DOI: 10.1016/j.topol.2003.10.011