Disseminating the new kilogram—an international 'dry run'
Tuesday, November 29, 2016 - 09:01
in Physics & Chemistry
When the kilogram, the world's basic unit of mass, gets a new definition in 2018, it will be based not on a physical artifact but a constant of nature. However, researchers will still need to "realize" the new definition, or translate it into a physical object, to make it possible to distribute the new standard to the laboratories and industries that need it. Of the two methods that are major contenders for this realization process – watt balances and silicon spheres – both require delicate measurements in vacuum.