Nuclear clock will be accurate over billions of years

A clock accurate to within a tenth of a second over 14 billion years -- the age of the universe -- is the goal of research being reported this week by scientists from three different institutions. To be published in the journal Physical Review Letters, the research provides the blueprint for a nuclear clock that would get its extreme accuracy from the nucleus of a single thorium ion.

Such a clock could be useful for certain forms of secure communication -- and perhaps of greater interest -- for studying the fundamental theories of physics. A nuclear clock could be as much as one hundred times more accurate than current atomic clocks, which now serve as the basis for the global positioning system (GPS) and a broad range of important measurements.