If I travel near the speed of light, form a stationary observer perspectives, I will take 1 year plus to travel 1 light year, but in my perspective, would I take less than 1 year to travel to that distance as my time slows down respect to stationary observer's time?

  • $\begingroup$ Yes. That is the concept of time dilation. $\endgroup$ – Jim May 14 '15 at 19:11
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    $\begingroup$ Yes. Please don't ask Yes/No questions, "yes" and "no" are too short to even submit as answers. $\endgroup$ – ACuriousMind May 14 '15 at 19:12
  • $\begingroup$ From your perspective the universe would flatten so that distances would appear less. You wouldn't think you're going faster than the speed of light but you'd see an object 4 light years away appear 3 light years away - for example. $\endgroup$ – userLTK May 14 '15 at 20:49
  • $\begingroup$ @Downvoter(s) Why downvote this valid question? $\endgroup$ – Jack Giffin May 5 '17 at 1:30

The observer sees you travel from A to B - a distance that, in his frame of reference, is greater than one light year. He sees that you take more than a year. He concludes you are traveling at less than the speed of light.

You, traveling so fast, "see" a much shorter distance (this is the concept of length contraction) $L' = L_0/\gamma$ where $\gamma = \frac{1}{\sqrt{1-v^2/c^2}}$ Your "on board" clock is also ticking more slowly: $T' = T_0 \gamma$. So while you think you took less than a year to get there, the speed with which you think you are approaching point B is the same speed that the observer (stationary at B) sees you approaching at. You too don't think you exceeded the speed of light.

If the stationary observer was using your clock and his length measurement, he might conclude you were traveling faster than the speed of light. But you can't just pick and choose - everything has to be determined in the same frame of reference.


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