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Affine hypersurfaces with parallel cubic form

Published online by Cambridge University Press:  22 January 2016

Franki Dillen
Affiliation:
Katholieke Universiteit Leuven, Departement Wiskunde, Celestijnenlaan 200 B, B-3001 Leuven, Belgium
Luc Vrancken
Affiliation:
Katholieke Universiteit Leuven, Departement Wiskunde, Celestijnenlaan 200 B, B-3001 Leuven, Belgium
Sahnur Yaprak
Affiliation:
Katholieke Universiteit Leuven, Departement Wiskunde, Celestijnenlaan 200 B, B-3001 Leuven, Belgium The University of Ankara, The Faculty of Sciences, Tandoḡan, 06100, Ankara, Turkey
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As is well known, there exists a canonical transversal vector field on a non-degenerate affine hypersurface M. This vector field is called the affine normal. The second fundamental form associated to this affine normal is called the affine metric. If M is locally strongly convex, then this affine metric is a Riemannian metric. And also, using the affine normal and the Gauss formula one can introduce an affine connection on M which is called the induced affine connection. Thus there are in general two different connections on M: one is the induced connection and the other is the Levi Civita connection of the affine metric h. The difference tensor K is defined by K(X, Y) = KXY — ∇XY — XY. The cubic form C is defined by C = ∇h and is related to the difference tensor by

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Type
Research Article
Copyright
Copyright © Editorial Board of Nagoya Mathematical Journal 1994

References

[D] Dillen, F., Equivalence theorems in affine differential geometry, Geom. Dedicata, 32 (1989), 8192.CrossRefGoogle Scholar
[DVl] Dillen, F., Vrancken, L., 3-dimensional affine hypersurfaces in R with parallel cubic form, Nagoya Math, J., 124 (1991), 4153.Google Scholar
[DV2] Dillen, F., Calabi-type composition of affine spheres, Diff. Geom. and Appl, (to appear).Google Scholar
[DV3] Dillen, F., The classification of 3-dimensional homogeneous locally strongly convex affine hypersurfaces, Manuscripta Math., 80 (1993), 165180.Google Scholar
[MN] Magid, M. and Nomizu, K., On affine surfaces whose cubic forms are parallel relative to the affine metric, Proc. Japan. Acad. Ser. A, 65 (1989), 215218.Google Scholar
[N] Nomizu, K., Introduction to affine differential geometry, Part I, MPI/88–38, Bonn, 1988, Revised: Department of Mathematics, Brown University, 1989.Google Scholar
[NS] Nomizu, K., Sasaki, T., A new model of unimodular-affinely homogeneous surfaces, Manuscripta Math., 73 (1991), 3944.CrossRefGoogle Scholar
[O’N] O’Neill, B., Semi-Riemannian geometry with applications to relativity, Academic Press, New York, 1983.Google Scholar
[VLS] Vrancken, L., Li, A.-M., Simon, U., Affine spheres with constant sectional curvature, Math. Z., 206 (1991), 651658.CrossRefGoogle Scholar