来自《耶鲁大学开放课程：基础物理 第12集 第12集》

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  So, it would have been possible
  因此 我们将有可能
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  to detect the velocity of the train
  测出火车的速度
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  without looking outside,
  不看外面
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  just by doing an experiment with light.
  仅仅通过做一个光的实验
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  So, even though mechanical laws involving F=m·a are the same,
  所以即使包括 F=m·a 在内的力学定律相同
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  laws of electricity and magnetism would be such
  电学和磁学的定律可能
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  that somehow they would betray your velocity.
  会泄露你所求的速度
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  And that would mean uniform velocity
  这意味着匀速运动
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  does make an observable change
  也会发生可观察的改变
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  because it changes the velocity of light that you would measure.
  因为你测量到的光速改变了
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  But conversely, the fact
  但是相反 事实是
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  that you keep getting the same answer means
  你一直得到相同的结果 这意味着