I read this in a write-up of an experiment using atomic clocks:
To reveal these effects, required the use of highly accurate atomic clocks, calibrated to check that they are perfectly in sync with each other – ticking down the nanoseconds (that's one billionth of a second: 0.000 000 001 seconds) in complete unison. One clock was taken on a trip around the world, whilst the other one stayed at the NPL in Teddington.
"When the two clocks were reunited, according to Einstein's theories, they should no longer be in sync - the clock that travelled around the world should be ahead of the stationary clock by a significant amount."
I thought the opposite would be true?
Am I correct?
Yes, you are quite correct. Congratulations for noticing that error by whoever wrote it.
Here is a more accurate press release about that experiment.
http://www3.open.ac.uk/media/fullstory.aspx?id=19636
Thanks Drwls, but that's the press release I spotted the error in. I think!
No, the statement in the write-up is correct. According to Einstein's theories of relativity, time can be affected by both motion and gravity. The experiment described in the write-up is known as the Hafele-Keating experiment, which was conducted in 1971.
In this experiment, two highly accurate atomic clocks were synchronized before one of them was taken on a trip around the world while the other remained stationary. When the two clocks were reunited, they indeed showed a time difference, with the clock that traveled around the world being slightly ahead of the stationary clock.
This outcome is known as time dilation, and it arises due to the relative motion between the two clocks. According to the theory of relativity, time moves slower for objects in motion compared to stationary objects. Therefore, the clock that traveled around the world experienced a slightly slower passage of time and ended up registering a slightly later time compared to the stationary clock.
This effect might seem counterintuitive, as one might expect the moving clock to experience time passing faster or be ahead of the stationary clock. However, the theory of relativity makes it clear that it is actually the other way around.
It's important to note that the time difference between the two clocks in this experiment is exceedingly small and would not be noticeable in daily life. However, accurate atomic clocks make it possible to measure such minuscule differences and provide evidence for the theory of relativity.