prof. Anna Szmyrka-Grzebyk, INTiBS PAN, Wrocław

New International System of Units

On 16 November 2018, the 26th General Conference on Weights and Measures (CGPM) approved the new International System of Units, SI. In the system, seven base units are defined by universal constants making it independent of the properties of matter, the place and time of realization of individual units. The four units - kilogram, ampere, kelvin and mole - are presently defined by the following physical constants: the Planck constant h, the elementary charge e, the Boltzmann constant k, the Avogadro constant NA.