Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-12-05T02:21:26.598Z Has data issue: false hasContentIssue false

An exotic totally real minimal immersion of S3 in ℂP3 and its characterisation

Published online by Cambridge University Press:  14 November 2011

B.-Y. Chen
Affiliation:
Department of Mathematics, Michigan State University, East Lansing, Michigan 48824-1027, U.S.A.
F. Dillen
Affiliation:
K.U. Leuven, Departement Wiskunde, Celestijnenlaan 200 B, B-3001 Leuven, Belgium
L. Verstraelen
Affiliation:
K.U. Leuven, Departement Wiskunde, Celestijnenlaan 200 B, B-3001 Leuven, Belgium
L. Vrancken
Affiliation:
K.U. Leuven, Departement Wiskunde, Celestijnenlaan 200 B, B-3001 Leuven, Belgium

Abstract

In a previous paper, B.-Y. Chen defined a Riemannian invariant δ by subtracting from the scalar curvature at every point of a Riemannian manifold the smallest sectional curvature at that point, and proved, for a submanifold of a real space form, a sharp inequality between δ and the mean curvature function. In this paper, we extend this inequality to totally real submanifolds of a complex space form. As a consequence, we obtain a metric obstruction for a Riemannian manifold Mn to admit a minimal totally real (i.e. Lagrangian) immersion into a complex space form of complex dimension n. Next we investigate three-dimensional submanifolds of the complex projective space ℂP3 which realise the equality in the inequality mentioned above. In particular, we construct and characterise a totally real minimal immersion of S3 in ℂP3.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1996

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

1Baikoussis, C. and Blair, D. E.. On the geometry of the 7-sphere. Resultate Math. 27 (1995), 516.Google Scholar
2Blair, D. E.. Contact Manifolds in Riemannian Geometry, Lecture Notes in Mathematics 509 (Berlin: Springer, 1976).Google Scholar
3Blair, D. E., Dillen, F., Verstraelen, L. and Vrancken, L.. Calabi curves as holomorphic Legendre curves and Chen's inequality. Kyungpook Math. J. 35 (1995) (to appear).Google Scholar
4Bolton, J., Jensen, G. R., Rigoli, M. and Woodward, L. M.. On conformal minimal immersions of S 2into CPn. Math. Ann. 279 (1988), 599620.CrossRefGoogle Scholar
5Chen, B.-Y.. Some pinching and classification theorems for minimal submanifolds. Arch. Math. 60 (1993), 568–78.Google Scholar
6Chen, B.-Y., Dillen, F., Verstraelen, L. and Vrancken, L.. Characterizing a class of totally real submanifolds of S6(l) by their sectional curvatures. Tohoku Math. J. 47 (1995), 185–98.CrossRefGoogle Scholar
7Chen, B.-Y., Dillen, F., Verstraelen, L. and Vrancken, L.. Totally real submanifolds of CPn satisfying a basic equality. Arch. Math. 63 (1994), 553–64.CrossRefGoogle Scholar
8Chen, B.-Y. and Oguie, K.. On totally real submanifolds. Trans. Amer. Math. Soc. 193 (1974), 257–66.CrossRefGoogle Scholar
9Dillen, F., Verstraelen, L. and Vrancken, L.. Classification of totally real 3-dimensional submanifolds of S6(l) with K S1/16. J. Math. Soc. Japan 42 (1990), 565–84.Google Scholar
10O'Neill, B.. Semi-Riemannian Geometry, with Applications to Relativity (New York: Academic Press, 1985).Google Scholar
11Reckziegel, H.. On the problem whether the image of a given differentiable map into a Riemannian manifold is contained in a submanifold with parallel second fundamental form. J. Reine. Angew. Math. 325(1981), 87104.Google Scholar
12Reckziegel, H.. Horizontal lifts of isometric immersions into the bundle space of a pseudo-Riemannian submersion. In Global Differential Geometry and Global Analysis (1984), Lecture Notes in Mathematics 1156, 264–79 (Berlin: Springer, 1985).CrossRefGoogle Scholar