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Bounding size of homotopy groups of Spheres

Published online by Cambridge University Press:  05 November 2020

Guy Boyde*
Affiliation:
Mathematical Sciences, University of Southampton, SouthamptonSO17 1BJ, UK (gb7g14@soton.ac.uk)

Abstract

Let p be prime. We prove that, for n odd, the p-torsion part of πq(Sn) has cardinality at most $p^{2^{{1}/({p-1})(q-n+3-2p)}}$ and hence has rank at most 21/(p−1)(qn+3−2p). for p = 2, these results also hold for n even. The best bounds proven in the existing literature are $p^{2^{q-n+1}}$ and 2qn+1, respectively, both due to Hans–Werner Henn. The main point of our result is therefore that the bound grows more slowly for larger primes. As a corollary of work of Henn, we obtain a similar result for the homotopy groups of a broader class of spaces.

MSC classification

Type
Research Article
Copyright
Copyright © The Author(s), 2020. Published by Cambridge University Press on Behalf of The Edinburgh Mathematical Society

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References

Bödigheimer, C.-F. and Henn, H.-W., A remark on the size of πq(Sn), Manuscripta Math. 42(1) (1983), 7983.CrossRefGoogle Scholar
Flajolet, P. and Prodinger, H., Level number sequences for trees, Discrete Math. 65(2) (1987), 149156.CrossRefGoogle Scholar
Henn, H.-W., On the growth of homotopy groups, Manuscripta Math. 56(2) (1986), 235245.CrossRefGoogle Scholar
Husemoller, D., Fibre bundles, 3rd ed., Graduate Texts in Mathematics, Vol. 20 (Springer-Verlag, New York, 1994).CrossRefGoogle Scholar
Iriye, K., On the ranks of homotopy groups of a space, Publ. Res. Inst. Math. Sci. 23(1) (1987), 209213.CrossRefGoogle Scholar
James, I. M., On the suspension sequence, Ann. Math. 65(2) (1957), 74107.CrossRefGoogle Scholar
Selick, P., A bound on the rank of πq(S n), Illinois J. Math. 26(2) (1982), 293295.CrossRefGoogle Scholar
Serre, J.-P., Homologie singulière des espaces fibrés, Appl. Ann. Math. 54(2) (1951), 425505.Google Scholar
Serre, J.-P., Groupes d'homotopie et classes de groupes abéliens, Ann. of Math. 58(2) (1953), 258294.CrossRefGoogle Scholar
Toda, H., On the double suspension E 2, J. Inst. Polytech. Osaka City Univ. Ser. A. 7 (1956), 103145.Google Scholar