Scientists Build First Nuclear Clocks, 1-Second Off in 30M Years

Scientists just built clocks so accurate they wouldn't lose a second even if they ran since the age of dinosaurs.

Two teams of researchers have independently created the world's first "nuclear clocks," devices that keep time by tracking incredibly tiny changes in the center of atoms. Published in the journal Nature, these experimental clocks represent a breakthrough scientists have been chasing for over two decades.

The clocks work by firing ultra-precise lasers at crystals containing a special type of thorium called thorium-229. Each laser pulse creates a microscopic "tick" at the atomic nucleus level, thousands of times smaller than what current atomic clocks can measure.

Right now, the nuclear clocks match the accuracy of today's best atomic clocks, losing just one second every 30 million years. But researchers say this is only the beginning.

"Nuclear clocks had the potential to become the most accurate instrument humans have ever built," said University of New South Wales physicist Victor Flambaum, who wasn't involved in the studies but called them an exciting breakthrough.

The key turning point came in early 2024 when Thorsten Schumm's team at Vienna University of Technology first managed to use a laser to change the state of an atomic nucleus. That discovery opened the floodgates. "The progress is so fast, I expect it will be soon" before nuclear clocks outperform atomic clocks, Professor Flambaum said.

Shiqian Ding from Tsinghua University, who led the other team, said building the clock required solving multiple problems at once. They needed to grow the right crystals, develop precise enough lasers, and figure out how to make everything work together reliably.

The Ripple Effect

These aren't just laboratory curiosities. Nuclear clocks could transform technology we use every day.

GPS systems would become far more accurate with better timekeeping. Professor Schumm envisions the clocks shrinking down to "chip-scale devices" small enough to carry anywhere, unlike today's room-sized atomic clocks.

The clocks could revolutionize mining by measuring subtle changes in Earth's gravitational field to reveal what lies underground. The same principle could help predict earthquakes by detecting tiny shifts in the planet's crust.

Perhaps most exciting, nuclear clocks could help solve one of physics' biggest mysteries: dark matter. Professor Schumm's team has already used their nuclear clock to detect evidence of this invisible substance that makes up most of the universe.

The technology could even test Einstein's theories of relativity by measuring how gravity manipulates time in previously impossible ways. Dr. Ding said he's "particularly excited about using nuclear clocks to test fundamental physics."

Multiple research teams worldwide are now racing to refine nuclear clocks and make them practical. Professor Schumm plans to install a second clock in Innsbruck within a year to measure subtle changes in Earth's movement around the Sun.

What started as a theoretical dream two decades ago is rapidly becoming reality, proving that sometimes the best way to move forward is to think really, really small.