摘要
利用数量曲率与第二基本形式长度之间的一个不等式关系,证明了其子流形的截面曲率一定非负(或者为正),并将此应用到紧致子流形上,得到一些结果.
By using an inequality relation between a scalar curvature and the length of the second fundamental form,it is proved that sectional curvatures of a submanifold must be nonnegative (or positive). Some results can be obtained with its application to compact submanifolds.
出处
《长沙电力学院学报(自然科学版)》
2004年第1期8-10,共3页
JOurnal of Changsha University of electric Power:Natural Science
关键词
数量曲率
截面曲率
不等式
紧致子流形
第二基本形式
平行法向量场
scalar curvature
sectional curvature
the second fundamental form
parallel normal vector field
minimal submanifold