Is the Langevin Twins Paradox Validated by Other Experiments?

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russ_watters said:
There is a difference between a clock and a tape measure that no one has picked-up on: a clock is a recording device (actually, two separate pieces: a measuring device and a recording device) and a tape measure isn't. Once a clock ticks off a second, that second is gone, never to be seen again. The only thing left is the record of that second, which for a clock is the time output by the display. So the measurements taken by a clock are exactly as permanent as those taken by a person with a clipboard standing over a tape measure. Better yet, one of those newfangled laser tape measures could keep a "permanent" record of length contraction.


no, clocks are a method of measure, they are not time itself. they make the passage of time but if you sping the hands backwords time doesn't reverse itself. clocks are exactly like a tape measure in that they both measure something. besides which, this is all totally besides the point.
 
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Gir said:
no, clocks are a method of measure, they are not time itself.
Um, I didn't say they 'are time'. I did say they are a measuring device. Did you read incorrectly? :confused:
sping the hands backwords time doesn't reverse itself. clocks are exactly like a tape measure in that they both measure something.
Again, that's all I was saying: that they are exactly like tape measures. So what's the problem? :confused:
 
Well, I feel it's good to question these things ... question everything. Okay, we have the observation ... we have the mathematical relationships describing it ... so, now let's do search for the mechanism causing it. Time is merely a measurement relative to a frame and something happens to that measurement ... relativity doesn't cause things ... there is a mechanism.
 
CeeAnne said:
Well, I feel it's good to question these things ... question everything. Okay, we have the observation ... we have the mathematical relationships describing it ... so, now let's do search for the mechanism causing it. Time is merely a measurement relative to a frame and something happens to that measurement ... relativity doesn't cause things ... there is a mechanism.

The mechanism is the postulate "laws of nature are equal to every inertial observer". If this wouldn't be true the laws of nature would be totally chaotic. From this postulate follows that the value of c has to be constant to every observer, since c defines the value of the interval. If the interval would be different to different observers, the maximum signal speed would also seem like changing, depending on the speed of the observer.

If c wouldn't be constant there could be photons with different velocities, same frequencies but different energies etc. It just wouldn't make sense.

And because c is constant to every inertial observer, time and length can't be absolute.
 
Hurkyl - your graphical analysis is appreciated - but I am still left without an answer to the question which concerns me. I will send you a private message since this thread is about to close