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Cohomology rings of almost-direct products of free groups

Published online by Cambridge University Press:  22 January 2010

Daniel C. Cohen*
Affiliation:
Department of Mathematics, Louisiana State University, Baton Rouge, LA 70803, USA (email: cohen@math.lsu.edu)
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Abstract

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An almost-direct product of free groups is an iterated semidirect product of finitely generated free groups in which the action of the constituent free groups on the homology of one another is trivial. We determine the structure of the cohomology ring of such a group. This is used to analyze the topological complexity of the associated Eilenberg–MacLane space.

Type
Research Article
Copyright
Copyright © Foundation Compositio Mathematica 2010

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