Scientists baffled as global benchmark to define kilo changes

THE guardians of the world’s most important standards of weights and measures have turned to quantum physics to try to resolve a dilemma.

To the bafflement of scientists, a cylinder of metal sitting in a closely-guarded strongbox that is the global benchmark for the kilogramme is changing mass.

The enigma doesn’t affect people who wants to buy 500mg tablets of aspirin, half a kilo of carrots or a 50,000-tonne cruise ship.