“Time is relative,” a concept proven by Albert Einstein over a century ago, is about to face its most rigorous test yet. The European Space Agency (ESA) launched a set of atomic clocks to the International Space Station (ISS) from Cape Canaveral, USA, on a SpaceX Falcon 9 rocket. This mission, a culmination of over 30 years of work, aims to measure time with unprecedented precision and scrutinize Einstein's theory of relativity.
Scientists will measure the effect of altitude on the passage of time. Since 1915, it has been known that time slows near massive objects. This 'Einstein effect,' though minuscule on Earth, becomes significant in space.
The ACES project, comprising two atomic clocks, will compare time measurements with nine terminals worldwide. These comparisons will determine if the results align with the predictions of relativity. A discrepancy could revolutionize physics, potentially reconciling general relativity and quantum mechanics, two currently incompatible theories.
Improved understanding of time dilation has practical applications. Satellite positioning systems like GPS and Galileo already account for relativistic effects to ensure accuracy. Enhancing the precision of these measurements could lead to more accurate navigation and timing technologies.