It would take 15 billion years for the clock that occupies Jun Ye’s basement lab at University of Colorado to lose a second—about how long universe has existed.
For this invention, the Chinese-American scientist, along side Hidetoshi Katori of Japan, will split $3 million as co-winners of 2022 Breakthrough Prize in Fundamental Physics.
Working independently, the 2 developed techniques using lasers to trap & cool atoms, then harness their vibrations to drive what are referred to as “optical lattice clocks,“ the foremost precise timekeeping pieces ever built.
By comparison, current atomic clocks lose a second once every 100 million years.
But what’s gained by greater accuracy?
“It’s really an instrument to permit you to probe basic-fabric of space-time in universe,” Ye told AFP.
In Ye’s lab, researchers have shown that times-moves slower when the clock is moved closer to bottom by a matter of centimeters, in line with Einstein’s predictions of relativity.
Applied to current technology, these clocks could improve GPS navigation accuracy by factor of thousand , or help smoothly land an unmanned spaceplane on Mars.
Brief history of time
Improving the precision & accuracy of timekeeping has been a goal since ancient Egyptians & Chinese made sundials.
A key breakthrough came with the invention of pendulum-clock in 1656, which relies on a swinging weight to keep-time, & a couple of decades later chronometers were accurate enough to find out a ship’s longitude at sea.
The early 20th century saw the arrival of quartz clocks, which when jolted with electricity resonate at very specific, high frequencies, or number of ticks during a second.
Quartz clocks are ubiquitous in modern electronics, but are still some-what vulnerable to variations caused by manufacturing process, or conditions like temperature.
The next great leap in timekeeping came from harnessing movements of energized atoms to develop atomic clocks, which are immune the consequences of such environmental variations.
Physicists know that one , very high frequency will cause particles called electrons that orbit the nucleus of a selected sort of atom to-jump to a higher-energy level , finding an orbit further faraway from the nucleus.
Atomic clocks generate the approx.. frequency that causes atoms of element Cesium to-jump thereto higher energy level .
Then, a detector counts the amount of these energized atoms, adjusting the frequency if necessary to form the clock more precise.
So precise that since 1967, one second has been defined as 9,192,631,770 oscillations of a Cesium atom.
Exploring the universe, and Earth
Katori’s & Ye’s labs have found ways to enhance atomic clocks even further by moving oscillations to the visible end of the electro-magnetic spectrum , with frequencies 100 thousand-times higher than those utilized in current atomic clocks—to make them even more accurate.
They realized they needed how to trap the atoms—in this case, of the element strontium—and hold them still with ultralow temperatures to assist measure time properly.
If the atoms are falling due-to-gravity or are otherwise moving, there would be a loss of accuracy, & relativity would cause distorting effects on timekeeping.
To trap atoms, the inventors created an “optical lattice” made by laser waves moving in-opposite directions to make a stationary, egg carton-like shape.
Ye is happy about the potential use of his clock. for instance , synchronizing the clocks of world’s best observatories down to tiniest fractions of a second would allow astronomers to-better conceptualize black-holes.
Better clocks also can shed new light on Earth’s geological processes.
Relativity tells us that point slows-down when it approaches a huge body, so a sufficiently accurate clock could tell scientists the difference between solid rock & volcanic lava below the surface, helping to predict an eruption.
Or indeed, measure the amount of oceans, or what proportion water flows beneath a desert.
The next great challenge, Ye says, are going to be miniaturizing the technology so it are often moved-out of a lab.
The scientist admits it’s sometimes hard to define fundamental physics concepts to the general public .
“But once they hear about clocks, they can feel it is a tangible thing, they might make a connection thereto , and that is very rewarding,” he said.