analogue of an n-sphere(英语:n-sphere) (with its canonical Riemannian metric(英语:Riemannian metric)). The main application of de Sitter space is its use in general
emissions graphic Google - public data(页面存档备份,存于互联网档案馆) "CO2 emissions (kt)" Google - public data(页面存档备份,存于互联网档案馆) "CO2 emissions (metric tons per capita)"