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On the Redefinition of the Kilogram



B N. Taylor, Peter Mohr


A new definition of the kilogram based on the Einstein relations E = mc^2 and E = hv is proposed, motivated by the recent progress at the National Institute of Standards and Technology in developing a moving-coil watt balance. Such a balance together with the definition promises to provide a practical means of directly calibrating standards of mass.


International System of Units, kg, kilogram, Planck constant, SI, watt balance


Taylor, B. and Mohr, P. (1998), On the Redefinition of the Kilogram, None (Accessed April 15, 2024)
Created August 5, 1998, Updated October 12, 2021