New posts in Metrology

How do you make more precise instruments while only using less precise instruments?

The definition of 1 kelvin

Why is the Planck constant an exact number with defined value?

What reference clock is an atomic clock measured against?

Why was the Planck constant $h$ fixed to be exactly $6.62607015\times10^{−34}\text{Js}$ and not some other value?

Can we determine the date just from sky observations?

How can I explain what a kilogram is using Planck's constant?

How can a day be exactly 24 hours long?

Will the SI units need redefining ever again?

In nuclear physics, what length year in seconds is used?