Scientists want to change the way a second is defined

Sign up for our free Health Check email to receive exclusive analysis on the week in health Get our free Health Check email Get our free Health Check email SIGN UP I would like to be emailed about offers, events and updates from The Independent. World still three minutes from ‘apocalypse’ according Doomsday Clock Dr Christian Grebing, of the The National Metrology Institute of Germany who worked on the new clock, said: “Our study is a milestone in terms of practical implementation of optical clocks. “The message is that we could today implement these optical clocks into the time-keeping infrastructure that we have now, and we would gain.” Optical clocks, which use lasers to monitor atoms or ions in a vacuum chamber shielded from outside influences, have been known about for some time but have been plagued with problems because they are so technically complicated and have a tendency to stop working. Dr Grebing said their method showed they could be made to work in a practically useful way, but added that formally redefining the length of a second should be delayed for perhaps another 10 years. “Probably the change would be less than the current uncertainty of a second defined by caesium atoms.”