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H2(T, G, ∂) and central extensions for crossed modules

Published online by Cambridge University Press:  20 January 2009

A. R.- Grandjean  and
M. Ladra
A. R.- Grandjean
Affiliation:
Departamento de Álgebra, Universidad de Santiago, Spain, E-mail addresses: [email protected] [email protected]
M. Ladra
Affiliation:
Departamento de Álgebra, Universidad de Santiago, Spain, E-mail addresses: [email protected] [email protected]
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We prove in this paper that if (T, G, ∂) is a perfect and aspherical (Ker ∂ = 1) crossed module, then it admits a universal central extension, whose kernel is the invariant H2(T, G, ∂), that we introduced in [9].

Type
Research Article
Information
Proceedings of the Edinburgh Mathematical Society , Volume 42 , Issue 1 , February 1999 , pp. 169 - 177
Copyright
Copyright © Edinburgh Mathematical Society 1999

References

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