Making the Tangible Intangible [Turnstile]

On 16 November 2018, international delegates at the General Conference on Weights and Measures in Versailles, France, unanimously voted to redefine the kilogram, the ampere, the kelvin, and the mole. The changes will take effect on 20 May 2019. The new kilogram will be based on Planck’s constant. One way to measure it will be a Kibble balance. Discusses the issues involved with these initiatives and examines the implications for scientific measurements.