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Counterexamples to a conjecture about spherical diagrams

Published online by Cambridge University Press:  24 October 2008

S. M. Gersten
Affiliation:
University of Utah, Salt Lake City, UT 84112, U.S.A.
James Howie
Affiliation:
University of Glasgow, Glasgow G12 8QW

Extract

A spherical diagram over a 2-complex X consists of a tessellation T of the 2-sphere, together with a combinatorial map (that is, one which maps each cell homeomorphically on to a cell). In [2] and [6] a number of conjectures were made concerning spherical diagrams over a 2-complex X with H2(X) = 0. There are also related conjectures in [7]. The motivation for all of these conjectures is that they imply the Kervaire Conjecture: every non-singular system of equations over a group can be solved in some overgroup (see [1, 2, 4, 6, 7] for details and discussion).

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1986

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References

REFERENCES

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