来自《耶鲁大学开放课程：基础物理 第13集 第13集》

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  Oh, but we've got to be careful.
  我们在这里要小心一点
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  So, his point had something to do with acceleration,
  这位同学提出的和加速度有关
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  but the real question is this:
  但真正的问题是
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  So if I'm on the ground and the same mate- the twin is on the trip and we meet,
  假设我在路上 与旅行回来的兄弟相遇
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  now the clocks have been compared.
  这时比较这两个钟
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  As long as the zigzag is going this way
  只要这块表往这边走 Z 字形
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  and that zigzag is going that way, you can say what you like.
  那块表往那边走 Z 字形 随你愿意
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  But what if the clocks are brought head-to-head and compared?
  但如果这两块表并排放一起相比较呢
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  Can they both be slower than the other? We know that's impossible.
  它们会比对方慢吗 我们知道这不可能
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  So, instead of clocks, we use human beings
  所以不用表 我们以人为例
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  and dramatize the paradox and say "Who will be younger?
  将这个悖论形象化 问"谁会较年轻
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  Me or the twin who went on the rocket?"
  是我还是那个去宇宙遨游的兄弟"