Now, the kilogram is defined in relation to the Planck constant, the smallest amount of energy a photon can carry. With this constant, scientists can make ultra-precise mass measurements using the ...

That’s pretty much all you need for instruments to determine Planck’s constant to a decent degree of precision, the way that [poblocki1982]’s did. There’s a little more to it, of course ...

It was 1900 before researchers succeeded in producing a comprehensive measurement of black-body radiation and the theoretician Max Planck established a radiation law that corresponded to these ...