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Time slowing down for someone traveling just under the speed of light 
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#1
Feb1213, 11:12 PM

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Lets say ship 1 is travelling just under the speed of light so time slows down for the crew and the age less quickly than the stationary crew in ship 2. Relative to the crew in ship 1, the crew of ship 2 are travelling at just under the speed of light, so time moves slower for them and they should be the ones aging more slowly. Which is it?



#2
Feb1213, 11:26 PM

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#3
Feb1313, 12:06 AM

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#4
Feb1313, 07:24 AM

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Time slowing down for someone traveling just under the speed of light



#5
Feb1313, 07:37 AM

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See for example the elaborations here: http://en.wikipedia.org/wiki/Time_di...ween_observers 


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Feb1313, 08:33 AM

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#7
Feb1313, 12:27 PM

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Feb1313, 12:35 PM

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#9
Feb1313, 02:05 PM

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http://math.ucr.edu/home/baez/physic...n_paradox.html In particular, the Doppler Shift Analysis and the Spacetime Diagram Analysis. The Doppler Shift Analysis focuses on what each twin actually sees, in the sense of the actual light signals each twin receives from the other; this might help in visualizing since it removes all the abstractions about "time dilation" and just focuses on the actual observations. The Spacetime Diagram Analysis gives a sort of "God's eye view" of what is happening and how it all fits together globally. 


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Feb1313, 02:29 PM

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#11
Feb1313, 03:58 PM

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#12
Feb1313, 04:17 PM

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1) The one your raised in your first post: When they're moving relative to one another, which one is "really" slow? The answer is "neither  they both see time passing more slowly for the other and there is no contradiction because of relativity of simultaneity". 2) The twin paradox: If they start out in the same place at the same time with the same age, travel for a while, then rejoin at a later time (which means that one of them has necessarily accelerated or freefallen through a fairly exciting gravitational field) so that they can directly compare their age, which one is younger? The answer here is that one of them will be unambiguously younger. 


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Feb1313, 09:54 PM

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