Is there any experimental evidence to support the concepts of time dilation and the twin paradox from Einstein's special theory of relativity?

eliasen

Yes, there's a huge amount of evidence for time dilation. There's no question that it happens. * Sensitive experiments show that at atomic clock in a rapidly-moving plane measures less time than a clock on the ground. To eliminate gravity effects (because you specified Special Relativity,) an airplane traveling east measures less time than a plane traveling west. (This is because the east-moving plane is moving *with* the earth's rotation, making its effective speed higher.) * If you accelerate a short-lived particle in a particle accelerator, (to almost the speed of light,) it 'lives' much longer because of time dilation. May 18 02, 5:54 PM

rlaj	This sounds like a question for DB. Apr 27 04, 1:46 PM

sequoianoir

This sounds like a question for Stephen Hawking. Apr 27 04, 2:01 PM

rlaj	If I understand the question, I have heard of something that might be the answer. I believe they put a watch on one of the moon missions and when it returned, it was off a a fraction of a second, thus providing evidence that time dilation is possible. Apr 27 04, 2:30 PM

sequoianoir

Apparently there is! The Twin paradox is a thought experiment in special relativity (SR): of two twin brothers, one undertakes a long space journey while the other remains on Earth. When the traveller finally returns to Earth, it is observed that he is younger than the twin who stayed put. The apparent paradox arises if one takes the position of the travelling twin: from his perspective, his brother on Earth is moving away quickly, and eventually comes close again. So the traveller can regard his brother on Earth to be a "moving clock" which should experience time dilation. Special relativity says that all observers are equivalent, and no particular frame of reference is privileged. Hence, the travelling twin, upon return to Earth, would expect to find his brother to be younger than himself, contrary to that brother's expectations. Which twin is correct? This outcome is predicted by special relativity ("time dilation of moving clocks") a phenomenon which has been verified experimentally, for example with muons produced in the upper atmosphere being detectable on the ground. Without time dilation, the muons would decay long before reaching the ground. Apr 27 04, 3:13 PM