The kilogram is a-shrinkin’ and ain’t nobody sure why. The problem is the way it is defined: the mass of a lump o’ metal stored in a vault in Paris. That’s no good cos a few atoms rub off each time it is picked up and others seem to fall off even when it ain’t picked up. In the last few years, it’s lost about the mass of a grain of sand.
Ain’t there a better way to define the kilogram? There sure is and shortage of em either. In November the world’s heavyweight experts are meeting in Paris to select the best definition by a vote or a toss of a coin or by some other method they ain’t told us about.
So between now and then expect to see plenty of elbowin’ n’ jostlin as the various definitions jockey for position. This week it’s the turn of Ronald “McDonald” Fox and Theodore “Over-the” Hill at Georgia Tech in Atlanta to pitch their definition.
They reckon that best way to define a kilogram is to fix the value of Avogadro’s constant, the number of atoms in 12 grams of carbon-12, at 84446886^3. That would make one gram exactly equal to the mass of 18 x 14074481^3 atoms of carbon-12.
It’s a good try but ain’t nobody gonna be happy with that definition. Why use carbon-12 and not silicon which is the current darling of most heavyweights in physics? And why rely on countin’ when you can define a kilogram in terms of its equivalent energy, thereby linking it via relativity to another fundamental: the Planck constant?
It’s all shapin up nicely for one helluva mudwrestle in Paris in November. All we need is a unit of hellraisin so we can work out the winner.
Ref: arxiv.org/abs/0709.2576: A Better Definition of the Kilogram