Ultraprecise atomic clocks put Einstein’s special relativity to the test

An experiment tested a foundational principle of physics known as Lorentz symmetry

atomic clock

WATCHING THE CLOCK  Scientists monitored two atomic clocks for six months in order to test a tenet of Einstein’s special theory of relativity. Each clock, like the one shown, contained a single ion of ytterbium.

PTB

The ticktock of two ultraprecise clocks has proven Einstein right, once again.