开放宇宙 meaning in Chinese

unbounded universe open universe

The size of an open universe is infinite and its geometry will be similar to a hyperbolic surface
开放宇宙是无限大的，而它的几何特性和双曲面相似。
The space geometry is open and negatively curved as a saddle . if the density equals to the critical density exactly , the space is flat as a sheet of paper . if the density is greater than the critical density , the space geometry is closed and positively curved as a ball
为负马鞍形的开放宇宙假若密度和临界密度相等，空间曲率为零，宇宙如一张白纸般平坦假若密度高于临界密度，它则是一个空间曲率为正球形的封闭宇宙。