John Barrett, The long way back (1947)
“ We say space is curved. We say a beam of light, if it went far enough would end up at its starting point. In fact, some astronomers say that nebulae in one part of the sky might be the same nebulae we see in another part of the sky, and we're actually seeing them twice because the light has traveled clear round the universe. Well, then, if the universe is curved and self-contained in one way, it must be curved and self-contained in every way. It's like the old symbol of the serpent swallowing its own tail."Carl looked over his shoulder. ”
