Global spacetime structure of compactified inflationary universe
Global spacetime structure of compactified inflationary universe
复制标题
致密暴胀宇宙的全球时空结构
DOI：
10.1088/1361-6382/ab38ed
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发表时间：
2019
影响因子：
3.5
通讯作者：
Yoshida Daisuke
中科院分区：
文献类型：
--
作者：
Numasawa Tokiro;Yoshida Daisuke
我们研究了环德西特宇宙的全局时空结构，这是基于平面图的环面识别的精确德西特空间。我们证明了环德西特宇宙中过去不完整的零测地线是局部可扩展的。然后我们给出环德西特宇宙的扩展，使得原始时空中至少一条过去不完整的零测地线变得完整。然而，我们发现扩展的德西特环面宇宙有两个不良行为。第一个是闭合因果曲线。第二个是所谓的准正则奇点，这意味着不存在所有曲线都完整的全局一致的时空扩展，但每条曲线都是局部可扩展的。
We investigate the global spacetime structure of torus de Sitter universe, which is exact de Sitter space with torus identification based on the flat chart. We show that past incomplete null geodesics in torus de Sitter universe are locally extendible. Then we give an extension of torus de Sitter universe so that at least one of the past incomplete null geodesics in the original spacetime becomes complete. However, we find that extended torus de Sitter universe has two ill behaviors. The first one is a closed causal curve. The second one is so called quasi regular singularity, which means that there is no global, consistent extension of spacetime where all curves become complete, nevertheless each curve is locally extensible.