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Differentiable Structures on the 15-Sphere and Pontrjagin Classes of Certain Manifolds

Published online by Cambridge University Press:  22 January 2016

Nobuo Shimada*
Affiliation:
Mathematical Institute, Nagoya University
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No manifold had been known which can carry two distinct differentiable structures until the recent important contribution due to J. Milnor [7] concerning the 7-sphere appeared.

In connection with his work, there are several problems, for example, about the existence of any other manifold with such property, about the topological invariance of the Pontrjagin classes of manifolds, etc.; some of them will be discussed in the present note.

Type
Research Article
Copyright
Copyright © Editorial Board of Nagoya Mathematical Journal 1957

References

[ 1 ] Borel, A. and Hirzebruch, F., On characteristic classes of homogeneous spaces, (to appear).Google Scholar
[ 2 ] Cartan, H., Séminaire de topologie algébrique, E.N.S. Paris, 19481949.Google Scholar
[ 3 ] Dold, A., Erzeugende der Thomschen Algebra ℜ Math. Z., 65 (1956), pp. 2535.Google Scholar
[ 4 ] Freudenthal, H., Oktaven, Ausnahmegruppen und Oktavengeometrie, Math. Instituut der Rijks-Universiteit, Utrecht, 1951.Google Scholar
[ 5 ] Hirzebruch, F., Neue topologische Methoden in der algebraischen Geometrie, Berlin, 1956.Google Scholar
[ 6 ] Hirzebruch, F., Some problems on differentiable and complex manifolds, Ann. of Math., 60 (1954), pp. 213236.Google Scholar
[ 7 ] Milnor, J., On manifolds homeomorphic to the 7-sphere, Ann. of Math., 64 (1956), pp. 399405.Google Scholar
[ 8 ] Reeb, G., Sur certain propriétés topologiques des variétés feuilletées, Actual, sci. industr., 1183, Paris, 1952, pp. 91154.Google Scholar
[ 9 ] Serre, J. P., Quelque calculs de groupes d’homotopie, C. R. 236 (1953), pp. 247577.Google Scholar
[10] Steenrod, N. E., The topology of fibre bundles, Princeton, 1951.Google Scholar
[11] Toda, H., Some relation in homotopy groups of spheres, Jour, of Inst. Polyt. Osaka City Univ., Vol. 2, No. 2 (1952), pp. 7180.Google Scholar
[12] Whitehead, G. W., On the homotopy groups of spheres and rotaion groups, Ann. of Math., 43 (1942), pp. 634640.Google Scholar
[13] Whitehead, G. W., On products in homotopy groups, Ann. of Math., 47 (1946), pp. 460475.Google Scholar
[14] Whitehead, G. W., A generalization of the Hopf invariant, Ann. of Math., 51 (1950), pp. 192237.Google Scholar
[15] Dold, A., Über fasernweise Homotopieäquivalenz von Faserraümen, Math. Z., 62 (1955), pp. 111136.Google Scholar
[16] Thorn, R., Les singularités des applications differentiates, Ann. de l’Institut Fourier, tome VI (19551956), pp. 4387.Google Scholar
[17] James, I. M. and Whitehead, J. H. C., The homotopy theory of sphere bundles (I), Proc. London Math. Soc., (3) 4 (1954), pp. 198218.Google Scholar
[18] Tamura, I., On Pontrjagin classes and homotopy types of manifolds, Jour, of Math. Soc. Japan, Vol. 9, No. 2 (1957), pp. 250262.Google Scholar
[19] Toda, H., Saito, Y. and Yokota, I., Note on the generator of π7(SO(n)), Memoirs of the College of Sci., Univ. of Kyoto, Series A, Vol. XXX, No. 3 (1957), pp. 227230.Google Scholar