brags said:
OK, I read your reply JesseM like 10 times and I think I see your point. Interesting...and totally beyond me for the most part. BUT, you mentioned the clocks. I have heard of this before, and I believe they measured atomic clocks on a space shuttle, or something to that affect, and they actually showed a slight time variation to those on earth. This blows my mind because clocks are mechanical/digital devices. How can they be affected by point of reference?
There isn't any easy conceptual answer to that question, it's just part of the fundamental laws of physics. Basically it has to do with the fact that all the fundamental equations of physics have a mathematical property called "Lorentz-symmetry" which insures that they will appear to work the same way in all reference frames.
brags said:
Besides, even if we ignore that, from the point of referrence of clock X which is nearing the speed of light, it would be standing still, and the universe around it would be traveling at near the speed of light towards it..so essentially to the clock its velocity would be nill, so why would it be ticking slower in referrence to an outside observer (clock Y) who is at a relative speed to the universe which clock X perceives is moving towards it?
This is another tricky part, there is no "objective" answer to which clock is ticking slower. In the rest frame of the galaxy, the moving clock is ticking slower than clocks at rest relative to the galaxy, but in the moving clock's own frame, the clocks at rest relative to the galaxy are the ones ticking slower. It might seem like this would lead to a contradiction--say I'm traveling past a row of clocks which are all at rest with respect to each other, and in the clocks' rest frame they are all synchronized to read 12:00 at the moment I pass the left end, and it takes me 25 minutes to pass them all, so they all read 12:25 at the moment I pass the right end. Now, say that my onboard clock also reads 12:00 at the moment I pass the left end, and that I'm moving at 0.6c relative to the clocks, so in their rest frame, my clock is only running at 0.8 the normal rate. An observer at rest relative to the clocks should predict that if the clocks measure the time for me to move from the left end to the right end as 25 minutes, then my own onboard clock should only tick forward by 0.8*25 = 20 minutes, so my clock will read 12:20 at the moment I pass the right clock. But if in my frame it's the row of clocks that are running at 0.8 the rate of my own clock, will I disagree with this prediction? The answer is no, because if the clocks are synchronized with each other in their own rest frame, they will
not appear synchronized in my own rest frame, due to what is known as the "relativity of simultaneity". This means that different frames disagree on whether two distant events happened "simultaneously" or not, so if the clock on the left end of the row and the clock at the right end of the row both read 12:00 "at the same time" in their own rest frame, this is not going to be true in my own frame. In my frame, at the moment I passed the clock on the left end which was reading 12:00, the clock on the right end already read 12:09, and in the 20 minutes it took me to reach the right end, that clock only advanced forward by 0.8*20 = 16 minutes, so when I reached it, it read 12:09 + 16 minutes = 12:25. So I agree that when I reached the right clock, it read 12:25 and my clock read 12:20, but in my frame this isn't because the clock on the right end was ticking faster than mine, it's just because the clock on the right end had a head start, due to it being out-of-sync with the clock on the left end.
