- #1
Lucretius
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(This isn't a homework problem, I'm struggling with this concept) My professor today was talking about time dilation. He stated that a clock that does not move in the observers point of view (a stationary clock) is, in that observer's viewpoint: a proper time. Thus, an observer on Earth will see a spaceship's clock tick slower, and thus less time will have elapsed on the ship than on Earth. So far so good for me. Here is what is tripping me up. We struggled with this for about five minutes, but felt we should just stop and think about it.
Let's say it took 10 years in the Earth frame and 6 years in the spaceship frame (the ship was traveling 80% light speed.) However, in the spaceship frame, the Earth is also moving away at 80% of light speed. If the spaceship sees his clock ticking at a normal rate (6 years), the Earth clock will be ticking slower (as all moving clocks do.) This will mean that the time for the Earth is less than six years, and not ten? And this could go on ad infinitum until both observers take zero time to go anywhere.
Obviously something has gone wrong with my thinking. But I can't quite pin it down. Both clock in their respective stationary frames represent proper times. Applying the time dilation formula I get these results. I can't figure this one out...
Let's say it took 10 years in the Earth frame and 6 years in the spaceship frame (the ship was traveling 80% light speed.) However, in the spaceship frame, the Earth is also moving away at 80% of light speed. If the spaceship sees his clock ticking at a normal rate (6 years), the Earth clock will be ticking slower (as all moving clocks do.) This will mean that the time for the Earth is less than six years, and not ten? And this could go on ad infinitum until both observers take zero time to go anywhere.
Obviously something has gone wrong with my thinking. But I can't quite pin it down. Both clock in their respective stationary frames represent proper times. Applying the time dilation formula I get these results. I can't figure this one out...