Three new almost positively curved manifolds

被引：1
作者：
DeVito, Jason [1 ]
机构：
[1] Univ Tennessee, Dept Math, Martin, TN 38238 USA
来源：
GEOMETRIAE DEDICATA | 2021年 / 212卷 / 01期
关键词：
Almost positive curvature; Homogeneous spaces; RIEMANNIAN-MANIFOLDS; CURVATURE; EXAMPLES; FAMILY;
D O I：
10.1007/s10711-020-00559-x
中图分类号：
O1 [数学];
学科分类号：
0701 ; 070101 ;
摘要：
A Riemannian manifold is called almost positively curved if the set of points for which all 2-planes have positive sectional curvature is open and dense. We find three new examples of almost positively curved manifolds: Sp(3)/Sp(1)(2), and two circle quotients of Sp(3)/Sp(1)(2). We also show the quasi-positively curved metric of Tapp (J Differ Geom 65:273-287, 2003) on Sp(n + 1)/Sp(n - 1) Sp(1) is not almost positively curved if n >= 3.
引用
收藏
页码：281 / 298
页数：18
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