FOR THE discerning timekeeper, solely an atomic clock will do. Whereas one of the best quartz timepieces will lose a millisecond each six weeks, an atomic clock won’t lose a thousandth of 1 in a decade. Such units underpin the whole lot from GPS and the internet to stock-market trading. Which will appear ok for many. However in a paper lately printed in Nature, researchers report being able to construct its successor: the nuclear clock. Ekkehard Peik, one of many area’s pioneers, says such a clock may very well be an element of 1,000 instances higher than right now’s customary atomic clocks.