The authors define the Gauss map of surfaces in the three-dimensional Heisenberg group and give a representation formula for surfaces of prescribed mean curvature.Furthermore,a second order partial differential equation for the Gauss map is obtained,and it is shown that this equation is the complete integrability condition of the representation.
We obtain an inequality in Sm×R and Hm×R which is similar to DDVV conjecture.As an application,we show that a minimal submanifold in H m×R with nonnegative scalar curvature must be a surface of the type γ×R,where γ is a geodesic in H m.In addition,we get a pinching theorem in Sm×R.
CHEN Qun 1,2 & CUI Qing 3,1,1 School of Mathematics and Statistics,Wuhan University,Wuhan 430079,China
In this article, we provide estimates for the degree of V bilipschitz determinacy of weighted homogeneous function germs defined on weighted homogeneous analytic variety V satisfying a convenient Lojasiewicz condition.The result gives an explicit order such that the geometrical structure of a weighted homogeneous polynomial function germs is preserved after higher order perturbations.
This paper concerns the submanifold geometry in the ambient space of warped productmanifolds F^n×_σR,this is a large family of manifolds including the usual space forms R^m S^m andH^m.We give the fundamental theorem for isometric immersions of hypersurfaces into warped productspace R^n×_σR,which extends this kind of results from the space forms and several spaces recentlyconsidered by Daniel to the cases of infinitely many ambient spaces.
Qun CHEN Cai Rong XIANG~1) School of Mathematics and Statistics, Wuhan University, Wuhan 430072, P.R. China