Physicists Just Created the World's Most Precise Clock—EverAshley Feinberg5/29/13 3:01pmFiled to: physicsatomic clockssciencetime403EditPromoteShare to KinjaToggle Conversation toolsGo to permalink We know that the universe is roughly 13.8 billion years old—give or take a few hundred million years. Which seems like a decently accurate reading. But a new pair of clocks, which can measure time at a 1018 fractional level, makes our own measurements look like child's play. To have the same level of precision as these twin timepieces, we'd have to be able to specify the age of the known universe to within less than one second.Tweaking an already wildly accurate method of telling time might seem a tad excessive. But a single second didn't just arise as an arbitrary measurement—it's based on an atom's frequency. And accurately measuring this doesn't come easy. Anything from a stray electric field to any movement of the atom whatsoever affects the measurement—small sources of error, sure, but error nonetheless.