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Topologies on locally compact groups

Published online by Cambridge University Press:  17 April 2009

Joan Cleary
Affiliation:
Department of Mathematics, La Trobe University, Bundoora, Vic. 3803, Australia
Sidney A. Morris
Affiliation:
Department of Mathematics, Statistics and Computing Science, The University of New England, Armidale, N.S.W. 2351, Australia
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Abstract

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Using the Iwasawa structure theorem for connected locally compact Hausdorff groups we show that every locally compact Hausdorff group G is homeomorphic to Rn × K × D, where n is a non-negative integer, K is a compact group and D is a discrete group. This makes recent results on cardinal numbers associated with the topology of locally compact groups more transparent. For abelian G, we note that the dual group, Ĝ, is homeomorphic to This leads us to the relationship card G = ω0(Ĝ) + 2ω0(G), where ω (respectively, ω0) denotes the weight (respectively local weight) of the topological group. From this classical results such as card G = 2 card Ĝ for compact Hausdorff abelian groups, and ω(G) = ω(Ĝ) for general locally compact Hausdorff abelian groups are easily derived.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1988

References

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