Abstract
We prove that for a compact subgroup H of a locally compact almost connected group G, the following properties are mutually equivalent: (1) H is a maximal compact subgroup of G, (2) the coset space G/H is \({\mathbb{Q}}\) -acyclic and \({\mathbb{Z}/2\mathbb{Z}}\) -acyclic in Čech cohomology, (3) G/H is contractible, (4) G/H is homeomorphic to a Euclidean space, (5) G/H is an absolute extensor for paracompact spaces, (6) G/H is a G-equivariant absolute extensor for paracompact proper G-spaces having a paracompact orbit space.
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Dedicated to the memory of Professor E.G. Skljarenko
S. A. Antonyan was supported by grant 165246 from CONACYT (Mexico).
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Antonyan, S.A. Characterizing maximal compact subgroups. Arch. Math. 98, 555–560 (2012). https://doi.org/10.1007/s00013-012-0389-8
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DOI: https://doi.org/10.1007/s00013-012-0389-8