And yet, being the last remaining, physical artifact in a club of fundamental SI units, the current definition of the kilogram has worn out. Most certainly the watt-balance will take its place ...

Brazilian researchers propose a new approach to a debate that has been going on among theoretical physicists for decades. They claim that the minimum number of standards needed to measure everything ...

The SI system includes a hierarchy of units to measure the amount of substance, accommodating a wide range of scales from kilomoles (kmol), which represent thousands of moles, down to picomoles (pmol) ...