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Cockcroft properties of graphs of 2-complexes

Published online by Cambridge University Press:  14 November 2011

N.D. Gilbert
Affiliation:
Department of Mathematics, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, Scotland, U.K.
James Howie
Affiliation:
Department of Mathematics, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, Scotland, U.K.

Abstract

Necessary and sufficient conditions are obtained for the 2-skeleton of the total space of a graph of 2-complexes to be Cockcroft, or L-Cockcroft for some subgroup L of the fundamental group. These conditions are used to construct new examples of Cockcroft and absolutely Cockcroft 2-complexes.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1994

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References

1Baik, Y.-G. and Pride, S. J.. Generators of the second homotopy module of presentations arising from group constructions (preprint, University of Glasgow, 1992).Google Scholar
2Baik, Y.-G., Howie, J. and Pride, S. J.. The identity problem for graph products of groups. J. Algebra 162(1993), 168–77.CrossRefGoogle Scholar
3Bogley, W. A. and Pride, S. J.. Aspherical relative presentations. Proc. Edinburgh Math. Soc. 35 (1992), 139.CrossRefGoogle Scholar
4Bogley, W. A.. Unions of Cockcroft 2-complexes. Proc. Edinburgh Math. Soc. (to appear).Google Scholar
5Dyer, M. N.. Cockcroft 2-complexes (preprint, University of Oregon, 1992).Google Scholar
6Gersten, S. M.. Dehn functions and l1-norms of finite presentations. In Algorithms and Classification in Combinatorial Group Theory, eds Baumslag, G. and Miller, C. F. III (Berlin: Springer, 1992).Google Scholar
7Gilbert, N. D. and Howie, J.. Threshold subgroups for Cockcroft 2-complexes. Comm. Algebra (to appear).Google Scholar
8Harlander, J.. Minimal Cockcroft subgroups. Glasgow Math. J. 36 (1994), 8790.CrossRefGoogle Scholar
9Howie, J.. On the asphericity of ribbon-disc complements. Trans. Amer. Math. Soc. 289(1985), 281302.CrossRefGoogle Scholar
10Pride, S. J.. An example of a presentation which is minimally Cockcroft in several different ways. J. Pure Appl. Algebra 88 (1993), 199204.CrossRefGoogle Scholar
11Scott, G. P. and Wall, C. T. C.. Topological methods in group theory. In Homological Group Theory, ed. Wall, C. T. C., London Mathematical Society Lecture Notes 36 (Cambridge: Cambridge University Press, 1979).Google Scholar