NIST Wants An Electronic Kilogram

Dearing writes "According to the Global Engineering Journal, NIST, those not-so-standard standards people, want to give up the hunk of metal they've been calling a kilogram, even though it never weighs the same twice. In it's place, an electronic kilogram could act as the permanent standard."

Comments

More information from NIST itself...

[aktbar]

(one of) NIST's own web page(s) on this is at http://www.eeel.nist.gov/811/elec-kilo.html. There's a lot more technical detail there than at the link given in the article.

This really does make sense to replace the artifact with something independent -- they have a bunch of "voodoo" every time they measure the current kilo to try to get the same answer.

Re:Why not define in terms of other standards?

[abde]

that wouldn't work - after all, then you've just scaled the problem down to ask "whats the weight of a proton"

remember that the base physical units have to be directly related not to theor, but to empirical observation. That's the difference between "units" and "physical quantities"

MASS is a physical quantity. "kilogram" is a "unit" of that quantity. defining it in terms of the "mass of a proton" makes no sense because thats essentially a *circular* argument.

if you;re gonna construct a vast edifice of science, the foundation better be damn rigorous! this isnt just semantics, its essential, the way that we have to be absolutely sure that 2 + 2 = 4 (which can be derived from the Completeness property of the Real number Set). A good reference for basic units and quantities is here.