Gravitation is the most tangible interaction of the four fundamental interactions of nature,
having been investigated long before the discovery of the electromagnetic, weak, and strong …

The redefinition of the SI unit of mass in terms of a fixed value of the Planck constant has
been made possible by the Kibble balance, previously known as the watt balance. Once the …

The special least-squares adjustment of the values of the fundamental constants, carried out
by the Committee on Data for Science and Technology (CODATA) in the summer of 2017, is …

On 16 November 2018 a revision of the International System of Units (the SI) was agreed by
the General Conference on Weights and Measures. The definitions of the base units were …

Topological materials are of interest to both fundamental science and advanced
technologies because topological states are robust with respect to perturbations and …

Abstract Researchers at the National Institute of Standards and Technology (NIST) have
measured the value of the Planck constant to be $\newcommand {\hres}{6.626\, 069\, 934 …

We present a summary of the Planck constant determinations using the NRC watt balance,
now referred to as the NRC Kibble balance. The summary includes a reanalysis of the four …

To determine the Avogadro constant NA by the x-ray crystal density method, the density of a
28 Si-enriched crystal was determined by absolute measurements of the mass and volume …

In 1922, Kottler put forward the program to remove the gravitational potential, the metric of
spacetime, from the fundamental equations in physics as far as possible. He successfully …

A tabletop-sized Kibble balance (KIBB-g1) designed to directly realize mass at the gram-
level range with uncertainties on the order of parts in 10 6 has been developed at the …