检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
作 者:李中林[1]
机构地区:[1]杭州大学数学系
出 处:《杭州大学学报(自然科学版)》1989年第3期237-244,共8页Journal of Hangzhou University Natural Science Edition
基 金:中国科学院科学基金资助课题
摘 要:本文讨论局部对称共形平坦Riemann流形N中的紧致H稳定子流形M,若M具于平行平均曲率向量场,则对M的截面曲率或Ricci曲率加上适当的限制条件后,我们证明了M是N中某全脐点子流形N^(N+1)的全脐点超曲面。In this paper, we establish the following theorems. Theorem 1. Let N be an (n + p)-dimensional locally symmetric, con-formally flat Riemannian manifold and M a p(>1)-codimensional compact H-stable submanifold immersed in N. If M is pseudo-umbilical with parallel mean curvature vector field and if the sectional curvature of M is greater than everywhere on M, then M is a totally umbilical hypersurface in an (n+1)-dimensional totally umbilical submanifold of N. Theorem 2. Suppose that N and M satisfy the condition of the theorem 1 with p≥1. If either the Ricci curvature of M is greater than or the Ricci curvature of M is not less than everywhere on M, then M is a totally umbilical hypersurface in an (n+1)-dimensional totally umbilical submanifold of N .
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:216.73.216.28