| 1. | Semi - symmetric spacelike hypersurfaces in de sitter space
空间中半对称的类空超曲面 |
| 2. | Compact maximal spacelike submanifolds in a de sitter space
空间中的紧致极大类空子流形 |
| 3. | Anti - de sitter space , although it is infinite , has a “ boundary , ” located out at infinity
反德西特空间虽然无穷大，却有个位于无穷远的“边界” 。 |
| 4. | A crucial aspect of anti - de sitter space is that it has a boundary where time is well defined
反德西特时空的一个特殊性质是它有个边界，边界上还有明确的时间轴。 |
| 5. | For four - dimensional anti - de sitter space , the boundary has two space dimensions and one time dimension
对于四维的反德西特空间来说，边界则是三维的，其中两维是空间，一维是时间。 |
| 6. | In particular , does anything similar hold for a universe like ours in place of the anti - de sitter space
尤其是类似的概念是否在和我们这个世界相似的宇宙中也成立，而不是仅出现在反德西特空间中？ |
| 7. | Just as the boundary of the escher print is a circle , the boundary of four - dimensional anti - de sitter space at any moment in time is a sphere
就如同艾雪版画的边界是个圆，四维反德西特空间的边界在任何时刻都是个二维的球。 |
| 8. | This paper contains three chapters . we discuss the pinching problems on the length of the second fundamental form of compact space - like submanifolds mn with unit parallel mean curvature vector in the de sitter space spn + p . in particular , a sufficient condition for mn with constant scalar curvature to be totally umbilical is given
讨论desitter空间s _ p ~ ( n + p )中具有平行的单位平均曲率向量的紧致类空子流形m ~ n的第二基本形式长度拼挤问题，给出了具有常数量曲率的这种子流形是全脐球面的一个充分条件。 |
