Unraveling the Time Dilation Argument: Does Speed Affect the Passage of Time?

[ghwellsjr]

Heh, I don't think I'm smart enough to pretend to know one way or the other. I'm still fairly confused. The more I think about it, the more mind-boggling it gets.

The current debate in my mind (yes, I'm crazy) is if our measurement of time via atomic clocks can change, like observing an electron changes what it will do (double slit experiment came to mind). And if it does or doesn't change, what effect does that have on reality... like aging?

I was having a hard time understanding the link posted on the first page. The "twin paradox" section seems to say (unless I misunderstood that too) that it's "only a paradox in that it appears inconsistent, but it's not." This leads me to believe that the time recorded would be different, but not reality (your age would remain the same as the person sitting still on Earth).

The other experiment, the Transverse Doppler Effect confuses me completely. I guess I'm just ignorant and need some sort of visual assistance.

So ignoring the TDE (^), I'm just going off of the "Twin Paradox," which lead me to that question: is it possible the measurement of time gives us the illusion (I know that's not a proper term to use) of time dilation, e.g.: 10 minutes on Earth ~= 9.99... minutes traveling extreme fast. Almost all of my confusion stems from the idea that I have a hard time wrapping my head around the fact that traveling at all, effectively makes you age slower, albeit negligible.

I apologize if these questions/posts are confusing.

The reason why it is called the Twin Paradox is because if you consider a trip where the traveling twin goes for 50 years away from Earth at a constant speed then turns around and comes back at the same constant speed for another 50 years, then during each half of the trip you have a symmetrical situation that can be easily analyzed from the FoR in which either twin is at rest. Then the other twin is the one that is experiencing slow time. So it appears, to those who ignore what happens in between (the twin turning around and no longer being at rest in the same FoR), that the experience of the twins is symmetrical all the time and that they should be the same age when the traveler comes home.

But you can't change your Frame of Reference in the middle of the scenario without incurring problems. The correct way to analyze this if you want to use one of the two frames in which the traveler is at rest for half the trip is to continue that same FoR for the other half of the trip. Then you will get the same answer that he is the one that has aged less when they reunite.

Note that unless they start out together and end up together, there is no single answer to which one ages less, different FoR's will give different answers.

 

[ghwellsjr]

Well I don't think it's realistic/feasible to actually test "aging" out (of anything, not necessarily living -- e.g. a metal ball suspended in water slowly rusting on Earth vs one in a fast shuttle over a long period of time... shuttle returns, compare results).

*Edit: That's actually really stupid example, but hopefully you get what I mean.

But people are saying that the guy on the fast trip would come back with a clock that's behind the stand-still one AND he would be younger than the stand-still Earth guy. The measurement of the clock I get, the age I don't, especially since "the fast-traveling guy would feel the same time passing by."

Is it just the measurement of time that changes or everything "time" encompasses? Cellular progression/decay slows down as well? That's the confusing part for me, but maybe I'm just looking at this from too simplistic of a viewpoint.

If you are correct, don't you think the guy in the shuttle taking a 100 year trip would find it rather awkward that his clock was running really slowly? He could notice if it was running at one-tenth of its normal rate while he was aging normally. So everything runs slower, clocks, rust rates, aging, cellular progression/decay, everything. One of the tenets of relativity is that you cannot tell how fast you are traveling and if you were correct, then that would be a way to tell, wouldn't it?

 

[Symbiosis]

The reason why it is called the Twin Paradox is because if you consider a trip where the traveling twin goes for 50 years away from Earth at a constant speed then turns around and comes back at the same constant speed for another 50 years, then during each half of the trip you have a symmetrical situation that can be easily analyzed from the FoR in which either twin is at rest. Then the other twin is the one that is experiencing slow time. So it appears, to those who ignore what happens in between (the twin turning around and no longer being at rest in the same FoR), that the experience of the twins is symmetrical all the time and that they should be the same age when the traveler comes home.

But you can't change your Frame of Reference in the middle of the scenario without incurring problems. The correct way to analyze this if you want to use one of the two frames in which the traveler is at rest for half the trip is to continue that same FoR for the other half of the trip. Then you will get the same answer that he is the one that has aged less when they reunite.

Note that unless they start out together and end up together, there is no single answer to which one ages less, different FoR's will give different answers.

Oh my god. Thank you. That finally clicked and made sense.

The only other question would be, what if it wasn't a trip away and back, but rather around the Earth for 50 years? *Edit: Never mind, you answered with your next post.

If you are correct, don't you think the guy in the shuttle taking a 100 year trip would find it rather awkward that his clock was running really slowly? He could notice if it was running at one-tenth of its normal rate while he was aging normally. So everything runs slower, clocks, rust rates, aging, cellular progression/decay, everything. One of the tenets of relativity is that you cannot tell how fast you are traveling and if you were correct, then that would be a way to tell, wouldn't it?

Touche.

SR is really painful. I really appreciate you guys taking the time to answer our elementary questions by the way.

 

[ghwellsjr]

Well we love the quick learners and you guys are about the quickest I have ever seen.

 

[Dale]

Well I don't think it's realistic/feasible to actually test "aging" out (of anything, not necessarily living -- e.g. a metal ball suspended in water slowly rusting on Earth vs one in a fast shuttle over a long period of time... shuttle returns, compare results).

However, it is feasible to do this test using rapidly decaying subatomic particles, such as muons. If you go to the "experimental basis" link I provided earlier and look for muons you can basically think of them as very small metal balls that rust extremely quickly.

Is it just the measurement of time that changes or everything "time" encompasses? Cellular progression/decay slows down as well? That's the confusing part for me, but maybe I'm just looking at this from too simplistic of a viewpoint.

All clocks dilate the same amount, regardless of whether they are atomic clocks pulsing, heart beats thumping, metal spheres rusting, or particles decaying. It is everything time encompasses.