J Geom Anal
DOI 10.1007/s12220-013-9418-5
Entire Conformal Killing Graphs in Foliated
Riemannian Spaces
Henrique F. de Lima · Joseilson R. de Lima ·
Marco Antonio L. Velásquez
Received: 23 October 2012
© Mathematica Josephina, Inc. 2013
Abstract We study the geometry of entire conformal Killing graphs, that is, graphs
constructed through the flow generated by a complete conformal Killing vector field
V and which are defined over an integral leaf of the foliation V
⊥
orthogonal to V . In
this setting, under a suitable restriction on the norm of the gradient of the function z
which determines such a graph Σ(z), we establish sufficient conditions to ensure that
Σ(z) is totally umbilical and, in particular, an integral leaf of V
⊥
.
Keywords Conformal Killing vector fields · Conformal Killing graphs · Totally
umbilical hypersurfaces · r th mean curvatures · Newton transformations
Mathematics Subject Classification 53C42 · 53C12
1 Introduction
Conformal Killing vector fields are important objects which have been widely used
in order to understand the geometry of submanifolds and, more particularly, of hy-
persurfaces immersed in Riemannian spaces. In this setting, Montiel [17] has studied
The first author is partially supported by CNPq, Brazil. The first and third authors are partially
supported by CAPES/CNPq, Brazil, grant Casadinho/Procad 552.464/2011-2.
The authors would like to thank the referee for giving some valuable suggestions which improved the
paper.
H.F. de Lima ( ) · J.R. de Lima · M.A.L. Velásquez
Departamento de Matemática e Estatística, Universidade Federal de Campina Grande,
58109-970 Campina Grande, Paraíba, Brazil
e-mail: henrique@dme.ufcg.edu.br
J.R. de Lima
e-mail: joseilson@dme.ufcg.edu.br
M.A.L. Velásquez
e-mail: marcolazarovelasquez@gmail.com