Abstract
In this short note we consider an n-dimensional compact Riemannian manifold (M, g) of constant scalar curvature S = n(n − 1)c and show that the presence of a nontrivial conformal vector field ξ on M forces S to be positive. Then we show that an appropriate control on the energy of ξ makes M to be isometric to the n-sphere S n(c).
Similar content being viewed by others
References
Amur K., Hedge V.S.: Conformality of Riemannian manifolds to spheres. J. Diff. Geom. 9, 571–576 (1974)
Besse A.L.: Einstein Manifolds. Springer, Berlin (1987)
Deshmukh S., Al-Solamy F.: Conformal gradient vector fields on a compact Riemannian manifold. Colloquium Math. 112(1), 157–161 (2008)
Obata M.: Conformal transformations of Riemannian manifolds. J. Diff. Geom. 4, 311–333 (1970)
Obata M.: Certain conditions for a Riemannian manifold to be isometric with a sphere. J. Math. Soc. Jpn. 14, 333–340 (1962)
Tanno S., Weber W.: Closed conformal vector fields. J. Diff. Geom. 3, 361–366 (1969)
Tashiro Y.: Complete Riemannian manifolds and some vector fields. Trans. Am. Math. Soc. 117, 251–275 (1965)
Author information
Authors and Affiliations
Corresponding author
Additional information
This work is supported by the Research center, College of Science, King Saud University.
Rights and permissions
About this article
Cite this article
Deshmukh, S. Characterizing spheres by conformal vector fields. Ann. Univ. Ferrara 56, 231–236 (2010). https://doi.org/10.1007/s11565-010-0101-5
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11565-010-0101-5