The clock on your wrist may be fairly accurate in everyday life, but it has nothing on atomic clocks. Scientists use atomic clocks for a variety of purposes, and the more accurate they are, the better they can provide useful data. But while the most common atomic clocks are an order of magnitude more accurate than your typical wall clock, they’re not perfect.
Now, a team of researchers has developed a clock that they claim is even more accurate than anything else in use today, dwarfing most other atomic clocks over a period of billions of years. That’s a bold claim, but scientists seem to have the data to back it up.
A number of factors make this new atomic clock more accurate than any clock before it. For starters, the team used ytterbium atoms instead of the more common cesium, which is often used in atomic clocks. Ytterbium oscillates 100,000 times more frequently per second than cesium, allowing smaller units of time to be measured.
On the top of that, the scientists used entangled particles for their clock. Quantum entanglement is a very bizarre property of quantum mechanics that essentially allows two particles to be measured by observing only one of them. Two entangled particles are connected by mechanisms that are still poorly understood and appear to receive information from each other at speeds faster than light, throwing classical physics out the window.
But in the case of this new atomic clock, the entangled atoms proved to be more precise in their oscillation than a random cloud of atoms would be, giving this atomic clock the added precision it needed to be a worthwhile endeavor.
“It’s as if the light serves as a communication link between atoms,” Chi Shu, co-author of the research, said in a statement. “The first atom that sees this light will modify the light slightly, and this light also modifies the second atom and the third atom, and through many cycles, the atoms collectively know each other and begin to behave similarly.”
Now this is not to say that modern atomic clocks are not good. In fact, the researchers note that if you were to start a modern atomic clock at the beginning of the birth of the universe – an estimated 13.8 billion years ago – and run it through today, it would be off by only about half a second. But if that same clock used entangled atoms like MIT’s new model, it would be off by less than 100 milliseconds, which is obviously a huge improvement.