Abstract
Our main result in this paper establishes that if G is a compact Lie subgroup of the isometry group of a compact Riemannian manifold M acting with cohomogeneity one in M and either G has no singular orbits or the singular orbits of G have dimension at most n−3, then the unit vector field N orthogonal to the principal orbits of G is weakly smooth and is a critical point of the energy functional acting on the unit normal vector fields of M. A formula for the energy of N in terms of the of integral of the Ricci curvature of M and of the integral of the square of the mean curvature of the principal orbits of G is obtained as well. In the case that M is the sphere and G the orthogonal group it is known that that N is minimizer. It is an open question if N is a minimizer in general.
Similar content being viewed by others
References
Borrelli, V., Brito, F., Gil-Medrano, O.: The infimum of the energy of unit vector fields on odd-dimensional spheres. Ann. Glob. Anal. Geom. 23, 129–140 (2003)
Brito, F.: Total bending of flows with mean curvature correction. Differ. Geom. Appl. 23, 157–163 (2000)
Brito, F., Walczak, P.: On the energy of unit vector fields with isolated singularities. Ann. Pol. Math. LXXIII(3), 269–274 (2000)
Federer, H.: Geometric Measure Theory. Springer, New York (1969)
Montgomery, D., Samuelson, H., Yang, C.T.: Exceptional orbits of highest dimension. Ann. Math. 64, 131–141 (1956)
Reilly, R.: Applications of the Hessian operator in a Riemannian manifold. Indiana Univ. Math. J. 26, 459–472 (1977)
Wiegmink, G.: Total bending of vector fields on Riemannian manifolds. Math. Ann. 303(2), 325–344 (1995)
Wood, C.M.: The energy of Hopf vector fields. Manuscr. Math. 101, 71–88 (2000)
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Nunes, G., Ripoll, J. A Note on the Infimum of Energy of Unit Vector Fields on a Compact Riemannian Manifold. J Geom Anal 18, 1088–1097 (2008). https://doi.org/10.1007/s12220-008-9046-7
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12220-008-9046-7