De Sitter空间S_1^(n+1)(1)的半平行及其高阶平行类空超曲面

The Semi-Parallel Spacelike Hypersurfaces and the Higher Order Parallel spacelike Hypersarfaces in S_1^(n+1)(1)

本文给出了DeSitter空间Sn + 11(1) (n >2 )的半平行超曲面的分类 ,并利用此分类定理证明了Sn + 1(1)的高阶平行超曲面与平行超曲面的等价性 .

In this paper,we get the classification of the semi-parallel hypersurfaces in a De Sitter space S n+1 1(1),(n>2),Using the classification,we obtain the equivalence between the hypersurfaces with parallel higher order fundamental form and the hypersurfces with parallel second fundamental form in S n+1 1(1).