The present state of the Avogadro project is, however, so promising that -- on the basis of new measurements with improved sphere interferometers -- the measurement uncertainty of 2 · 10 -8 demanded ...

An ongoing international effort to redefine the kilogram by 2018 has been helped by recent efforts from a team researchers from Italy, Japan and Germany to correlate two of the most precise ...

The number of atoms in this silicon sphere is known given or taken 20 atoms each 109. The atom distance was measured by the X-ray interferometer on the left. (Credit: Enrico Massa and Carlo Sasso) ...

The kilogram is a massive headache for scientists. It is officially defined as the mass of a 122-year-old cylinder of platinum and iridium, kept at the International Bureau of Weights and Measures ...

This release is available in German. A milestone in the international Avogadro project coordinated by the Physikalisch-Technische Bundesanstalt (PTB) has been reached: With the aid of a single crystal ...