The commutator subgroup of a free topological group need not be projective
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- Proc. Amer. Math. Soc. 57 (1976), 354-356 Request permission
Abstract:
It is shown that the commutator subgroup of the free topological group on the $n$-sphere is, for $n > 1$, not projective and hence not free topological. The proof depends on the computation of the $\bmod 2$ cohomology ring of the classifying space of the commutator subgroup.References
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Additional Information
- © Copyright 1976 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 57 (1976), 354-356
- MSC: Primary 22A05
- DOI: https://doi.org/10.1090/S0002-9939-1976-0404512-2
- MathSciNet review: 0404512