可是对站在飞船之外、正在观看飞船运行的人们来说，这个车头灯并没有点亮：车头灯所发出的光到达观察者需要无穷大的时间，因为要求车头灯所发出的光束的速度超过以光速运行的飞船是不可能的。
For someone standing outside watching the ship fly by, the headlights do not appear to turn on: light comes out but it takes an eternity for the beams to get ahead of the spaceship.
目前为止的例子都是使用缺省形状拣选对象：可以假想是一根从观察者眼睛的位置经过鼠标点至无穷远处的射线。
So far the examples have picked objects using the default shape: an imaginary ray going from the viewer's eye position through the mouse pointer into infinity.
它表明了两者无穷大的范围是恰好相同的，从这个意义上来说，“一对一”的对应法可用于两者之间。
It says they are infinite to precisely the same extent, in the sense that a "one-to-one correspondence" can be established between them.
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