Now we have three conflicting reports: Bertha sees the light hit both targets at once; you see one of the targets get hit first; and Larry, who is probably surprised to find you out in space doing physics experiments, sees the other target get hit first. And you’re all correct! Not only do we have to accept that there is a top speed in the universe, but we have to give up the idea that events happen at the same time for everyone everywhere. No longer can we even assume the very reasonable-sounding idea that there is a single agreed-upon description of what happens in our universe. It all
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