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Ther was an experiment where scientists built two ultra precise clocks. One of them stayed on earth while the other was sent to space orbiting the earth at much

Ther was an experiment where scientists built two ultra precise clocks. One of them stayed on earth while the other was sent to space orbiting the earth at much higher speed than the one left behind. Once the clock from space was returned scientist observed that time on the clock in space progressed slower relative to the on the one from earth. Which proves Einstein's predictions based on General Theory Of Relativity. This is being considered when e.g. sending probes to Mars.

MichaelApproved 6y ago
It was also done with planes flying around the world. https://en.m.wikipedia.org/wiki/Hafele–Keating_experiment https://en.m.wikipedia.org/wiki/Hafele–Keating_experiment > The Hafele–Keating experiment was a test of the theory of relativity. In October 1971, Joseph C. Hafele, a physicist, and Richard E. Keating, an astronomer, took four cesium-beam atomic clocks aboard commercial airliners. They flew twice around the world, first eastward, then westward, and compared the clocks against others that remained at the United States Naval Observatory. When reunited, the three sets of clocks were found to disagree with one another, and their differences were consistent with the predictions of special and general relativity. —— Also, GPS wouldn’t work without understanding relativity because the clocks in the satellites move faster (I think?) than the ones here on Earth.
- imglorp 6y ago
  And even locating a clock to a higher elevation, because gravitational curvature has the same effect as relative motion. https://arxiv.org/pdf/1710.07381.pdf https://arxiv.org/pdf/1710.07381.pdf Can't find the reference now but even moving the clock a few meters is a measurable drift.
toxicFork 6y ago
It's also considered with the GPS :) http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps.html http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps....
lapetitejort 6y ago
Atomic clocks are so sensitive now that it's possible to desync them while they're in the same room [0] [0]: https://www.nist.gov/news-events/news/2010/09/nist-pair-aluminum-atomic-clocks-reveal-einsteins-relativity-personal-scale https://www.nist.gov/news-events/news/2010/09/nist-pair-alum...

MichaelApproved 6y ago

It was also done with planes flying around the world. https://en.m.wikipedia.org/wiki/Hafele–Keating_experiment https://en.m.wikipedia.org/wiki/Hafele–Keating_experiment > The Hafele–Keating experiment was a test of the theory of relativity. In October 1971, Joseph C. Hafele, a physicist, and Richard E. Keating, an astronomer, took four cesium-beam atomic clocks aboard commercial airliners. They flew twice around the world, first eastward, then westward, and compared the clocks against others that remained at the United States Naval Observatory. When reunited, the three sets of clocks were found to disagree with one another, and their differences were consistent with the predictions of special and general relativity. —— Also, GPS wouldn’t work without understanding relativity because the clocks in the satellites move faster (I think?) than the ones here on Earth.

imglorp 6y ago
And even locating a clock to a higher elevation, because gravitational curvature has the same effect as relative motion. https://arxiv.org/pdf/1710.07381.pdf https://arxiv.org/pdf/1710.07381.pdf Can't find the reference now but even moving the clock a few meters is a measurable drift.

toxicFork 6y ago

It's also considered with the GPS :) http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps.html http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps....

lapetitejort 6y ago

Atomic clocks are so sensitive now that it's possible to desync them while they're in the same room [0] [0]: https://www.nist.gov/news-events/news/2010/09/nist-pair-aluminum-atomic-clocks-reveal-einsteins-relativity-personal-scale https://www.nist.gov/news-events/news/2010/09/nist-pair-alum...