第一。 closing speed 这只是这些列出的超光速运动之一。。 达到近2倍光速。。special relativity does not prohibit this。 closing speed 不是在给超光速的反例
第二。It tells us that it is wrong to use Galilean relativity to compute the velocity of one of the particles, as would be measured by an observer traveling alongside the other particle. That is, special relativity gives the right formula for computing such relative velocity.
给你简单的翻译一下。侠义相对论认为如果从与另一个粒子同行的观察者角度测量，用伽利略相对性来计算其中一个粒子的速度，那是错误的。
这句是说 it tell us 中的it。是指special relativity。
as would be measured by an observer traveling alongside the other particle. 这句话给出了参照系。
That is, special relativity gives the right formula for computing such relative velocity. 狭义相对论对这样的相对速度有正确的公式。。
