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Lifting amalgamated sums and other colimits of groups and topological groups

Published online by Cambridge University Press:  24 October 2008

Ronald Brown
Affiliation:
Department of Pure Mathematics, University College of North Wales, Bangor, Gwynedd LL57 2UW
Philip R. Heath
Affiliation:
Department of Mathematics, Memorial University of Newfoundland, St John's, Newfoundland A1C 5S7, Canada

Extract

Suppose a group H is given as a free product with amalgamation

determined by groups A0, A1, A2 and homomorphisms α1: A0A1, α2: A0A2. Thus H may be described as the quotient of the free product A * A2 by the relations i1 α10) = i2α20) for all α0A0, where i1, i2 are the two injections of A1, A2 into A1 * A2. We do not assume that α1, α2 are injective, so the canonical homomorphisms α′i: AiH, i = 0,1,2, also need not be injective.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1987

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References

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