伪脐子流形的两个Pinching定理  

Two Pinching theorems for pseudo-umbilical submanifolds

作　　者：纪永强[1] 

机构地区：[1]湖州师范学院数学系,浙江湖州313000

出　　处：《海南师范学院学报（自然科学版）》2005年第1期12-15,20,共5页Journal of Hainan Normal University:Natural Science

摘　　要：设Mn+p+q2是n+p+q维拟常曲率的黎曼流形,Mn+p1(c1)为Mn+p+q2中的n+p维常曲率为c1的子流形,Mn为Mn+p1(c1)中具有平行平均曲率向量的紧致伪脐子流形,给出了Mn是Mn+p1(c1)的全脐子流形的几个充分条件.Let M^(n+p+q)_2 be a (n+p+q)-dimensional quasi-constant curvature Riemannian manifold and M^(n+p)_1(c_1) be a (n+p)-dimensional with constant curvature c_1 in M^(n+p+q)_2,and let M^n be a compact pseudo-umbilical submanifold with parallel mean curvature vector in M^(n+p)_1(c_1),we give some sufficient conditions for M^n to be a totally umbilical submanifold in M^(n+p)_1(c_1).

关 键 词：拟常曲率流形 伪脐子流形 全脐子流形 

分 类 号：O186.12[理学—数学]