What are atomic clocks?

Atomic clocks are the most precise timekeepers in the world. These exquisite instruments use lasers to measure the vibrations of atoms, which oscillate at a constant frequency, like many microscopic pendulums swinging in sync. The best atomic clocks in the world keep time with such precision that, if they had been running since the beginning of the universe, they would only be off by about half a second today.


Entangled clocks

In their new atomic clock, the team of researchers at MIT entangle around 350 atoms of ytterbium, which oscillates at the same very high frequency as visible light, meaning any one atom vibrates 100,000 times more often in one second than cesium. They used standard techniques to cool the atoms and trap them in an optical cavity formed by two mirrors, then sent a laser through the optical cavity, where it ping-ponged between the mirrors, interacting with the atoms thousands of times.

The researchers quantumly entangle the atoms, then use another laser to measure their average frequency.


What it means

With better atomic clocks, scientists could also start to answer some mind-bending questions, such as what effect gravity might have on the passage of time and whether time itself changes as the universe ages.

As the universe ages, does the speed of light change? Does the charge of the electron change? That’s what you can probe with more precise atomic clocks.


A new atomic clock

A newly-designed atomic clock, by MIT physicists, uses entangled atoms to keep time even more precisely than its state-of-the-art counterparts. The design could help scientists detect dark matter and study gravity’s effect on time. The new setup can achieve the same precision four times faster than clocks without entanglement.


A robot dance party

Have you ever seen a robot strut its funky stuff? Boston Dynamics just held a robot dance party and the robots showed amazing moves.

In a recent video posted to YouTube and Twitter, the Boston Dynamics Atlas robot is seen jamming to “Do you love me” by The Contours before it is joined by another Atlas, their trusty sidekick, Spot the robot dog, and eventually a Handle robot to create the most surreal, but amazing dance party.

In fact, the moves are so impressive that some users have taken to Twitter to claim the whole video is CGI.

However, the movements are legit. It definitely gives a new meaning to the dance floor classic, “the robot”.

Published in Dawn, Young World, January 9th, 2021

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