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Atom counting helps kilogram watch its weight

点击量:   时间:2019-03-07 03:05:04

LISTEN up, weight watchers. The most accurate count of atoms ever made could speed the switch to a new definition of a kilogram. This October, a committee in Paris, France, is expected to begin the process of defining the kilogram in terms of fundamental constants, rather than the physical artefact used today. The front-running definition uses an instrument called a Watt balance to derive a value for the Planck constant, which can be related to the kilogram. But this week,