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I A question about the time

  1. Aug 22, 2015 #1
    Consider two clocks in two frames.First time they meet each other and we adjust the index of the needles the same number.After that they move apart each other.If there is an Angel who stands at one clock and observes two clocks.Suppose the Angel directly sees distant clock,but needs not to adjust the time that the light travel from the clock to the eyes of the Angel.What does the Angel see the two clocks?.Does the needles point different or same number in the eyes of the Angel?I think that certainly there is a difference in the eyes of the Angel and the Man.If in the eyes of Angel the two locks point different number then we meet the contradictions because we are freely to choose which clock being in motion.
    Last edited: Aug 22, 2015
  2. jcsd
  3. Aug 22, 2015 #2


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    He sees the moving clock tick more slowly. He sees the needle of the moving clock point to a smaller number.

    If I understand you, you imagine two clocks A and B, and an Angel who stands beside clock A. The other clock, B, moves away from where the Angel and clock A are. You say to imagine that the Angel can read both clocks, instantaneously. Neglect the time it takes for light to travel to him from clock B, that is moving away. Somehow he can tell what clock B says. So at any given moment he can tell what both clocks say.
    Last edited: Aug 22, 2015
  4. Aug 22, 2015 #3


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    Special relativity says that this is impossible. It doesn't make sense to state an assumption that is inconsistent with a theory, and then ask what a theory predicts under that assumption.
  5. Aug 22, 2015 #4


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    As bcrowell said.

    Thread closed.
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