Hostname: page-component-cd9895bd7-gbm5v Total loading time: 0 Render date: 2024-12-26T08:52:13.438Z Has data issue: false hasContentIssue false

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 ([email protected])

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

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

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