If there's a fundamental unit of time at the tiniest scales of the universe, it's too small to measure. But scientists found what its upper limit must be.

The time it took for a photo to pass through a hydrogen molecule was measured at 247 zeptoseconds, which is the smallest measurement ever achieved.

Scientists have measured the shortest unit of time ever, the time it takes for a particle of light to cross a hydrogen molecule.

They measured how long it takes for a photon to cross a hydrogen molecule - around 247 zeptoseconds - making this measurement the shortest time span EVER to have been successfully recorded.

A team of physicists have recorded the shortest possible measurement of time: the zeptosecond. A zeptosecond is a trillionth of a billionth of a second. Or, to give it its numerical value: 0. ...

Scientists said that "zeptosecond" is the smallest amount of time. The new unit represents one trillionth of a billionth of a second (10 to the -21st power), which is smaller than a millisecond ...

A zeptosecond, the shortest amount of time ever recorded, has just been measured by scientists. It represent one trillionth of a billionth of a second (10 -21 seconds). Physicists from Goethe ...

Physicists have for the first time coaxed two atoms in separate locations to take turns jiggling back and forth while swapping the smallest measurable units of energy. By directly linking the ...

Most of us think of a microsecond or a nanosecond as being about as brief as time measurements get - but German scientists have gone quite a bit better. This week, atomic physicists measured a process ...