08 Sep 2010

Bang Goes The Theory demonstrates Einstein's Theory of Relativity

Bang Goes The Theory returns for another series

Bang Goes The Theory returns for another series

This summer an atomic clock held at the National Physical Laboratory (NPL) in Teddington was flown around the world by BBC One’s Bang Goes The Theory, produced in partnership with The Open University, in the first televised test of Einstein’s Theory of Relativity.

In an extremely rare test of Einstein’s greatest theory, the clock flew for 800km over fifty hours and was found to have slowed by 230 ± 20 nanoseconds, compared to an atomic clock that stayed in exactly the same position at the NPL in Teddington.

The experiment was a repeat of the famous Hafele-Keating experiment and revealed the time dilation effects predicted by Einstein's Theory of Relativity.

Bang Goes The Theory presenter, Dallas Campbell accompanied the clock on its lengthy journey: “Hopefully we’ve demonstrated that you don’t need a Delorian and a Flux Capacitor to have your own mini Back To The Future adventure. I’m hoping that the extra 250 nanoseconds doesn’t show, but it’s a small price to pay to prove that time really does fly when you’re having fun.”

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.

The results demonstrate that Einstein's theories are correct, as Bang Goes The Theory and the NPL were able to measure a clear time-shift of 230 ± 20 nanoseconds between the two clocks involved in the experiment. This agrees with the time-shift predicted by Einstein.

The new series of Bang Goes The Theory starts at 7.30pm, Wednesday 8 September on BBC ONE.

Notes To Editors:

Bang Goes The Theory was co-produced by The Open University.

Pictures available from

To continue the learning journey with The Open University, visit and follow the links to the Open University website.

To download a Bang Goes The Theory screensaver, go to:

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