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New Book Says The Meter Is all Wrong
Bill Klemm writes "Ken Alder's new book 'The Measure of All Things' scandalizes the metric system as 'arbitrary.' CNN has a little article about a new book that explores the 'odyssey' of Delambre and Mechain to find the perfect unit of measure."
0 degrees - the energy at which a hydrogen atom is at rest. 1 degree would be the energy at which hydrogen is one quantum state higher than rest.
1 length - the distance across 1 hydrogen atom
1 time unit - the time required for a hydrogen nucleus to vibrate once
Then you can apply whatever kind of metric multiples you like to these and voila, you are done.
A quote:
"I remember my fifth-grade teacher instructing us in the metric system and telling us we would need to learn this material because we would all be using it in the future," he says. "I believed her, of course. And when that future failed to arrive I began to wonder why.
He should get a clue, the rest of the world uses the metric system, this future has materialized. If one country wants to be stubborn and hold out, whatever.
Anyhow, the real beauty of the metric system is that it's various units of measurements make sense. As in, a centimeter is a hundredth of a meter, a millimeter is a thousands of a meter, etc. The imperial system wouldn't be so strange if it was 10 inches to a foot, but it's not.
Anyhow, the meter is not the only part of the metric system, it also encompasses temperature, weight, etc. And the meter is certainly less arbitrary than the foot!
In meters, for example, mathmeticians had to use a definition that allowed others acrossed the world to also come up with an exact length. If these mathemeticians truly wanted a non-arbitrary system back then, they could have made a "master meter stick", whose length was not based on anything arbitrary. But such a system would never work, because then they would have had to ship copies of the master meter stick across the world. The ratio system was much more practical.
Mass and volume are arbitarary in 2 ways. They rely off our arbitary meter, as well as the arbitary earth's gravity. A definition I've heard is that 1 cubic centimeter of water at sea level weights 1 gram and has a volume of 1 mL. Try taking a cubic centimeter of water to a different world, and you'll get different measurements. Today, the official definition of a kilogram is the mass of an international prototype in the form of a platinum-iridium cylinder kept at Sevres in France. (By the way, you could also say that using water is also arbitrary, since we earthlings used a commonly found liquid. The sea level is also arbitrary, since it varies across different coasts, as well over time)
Temperature is also based off the arbitary earth's atmosphere. 0 degrees Celsius is the freezing point of water at 1 atm (the standard air pressure of earth). If you increase or decrease the pressure, you'll get different freezing points.
Anyways, my point is, that it was next to impossible to come up with a practical system without it being arbitrary in some way or another.
P.S. If anything in this article needs correction, please correct it. I'm probably wrong somewhere since everything I said was what I remember from years ago.
Well, france and a bunch of other countries kinda just said "okay everyone, we're going to use Metric for everything now!" (but they said it in french. it probably sounded smoother).
Is switching to the unit system everybody else uses on earth harder than say, switch to an arbitrary new currency like the Euro?
Some would argue the US did make it harder for itself by waiting so long. In the end, it's really a matter of motivation.
As long the US doesn't see a need to follow what other countries are doing, things won't change.
That is the real reason, more than "oh well, it's kinda hard to do".
It will be a sign of a major change of attitude when the US finally decides to do the switch.
Who knows what will be next? ratifying a kyoto treaty? playing nice with the other kids^H^H^H^Hnations at the UN? The possibilities are endless.
Multiplied by 2, divided by 2.
I'll stake my cat this is in use already.
0 degrees - the energy at which a hydrogen atom is at rest. 1 degree would be the energy at which hydrogen is one quantum state higher than rest.
By saying "degrees" I take it you are referring to temperature... but energy is NOT the same thing as temperature, even though they are often linked. I believe you're thinking of something more along the lines of electron-volts (eV). The "volt" is what you'd need to re-define in order to normalize your energy scale with respect to this bound electron.
However, some people might find that saying "the nearest gas station is about 1x10^15 distances away" a tad bit inconvenient. Atoms are pretty "fuzzy" anyway so the only length you can go by is the bohr radius, which is an oversimplification of the actual probalistic structure of a hydrogen atom. But if we want to develop units from the atomic scale, wouldn't it be better to define length as the distance travelled by light in a vacuum during the time it takes hydrogen to "vibrate" once?
As for the hydrogen's rest energy, well that is essentially defined by its mass (times speed of light squared). So maybe it's better to define a hydrogen atom as having a mass unit of 1 and then derive energy from that.
Hmmm.... wait a minute, hydrogen is just a proton and an electron. Electrons have negligible mass compared to a proton. Why don't we just call the mass of a proton "1 mass unit," that makes more sense because the proton is even more fundamental than hydrogen.
If you think that's the best idea, then you're in luck, because that unit of measure has already been invented! The atomic mass! Well, sort of, since a proton has an atomic mass of 1.0073, and when you add the atomic mass of an electron, you get a value slightly higher than the atomic mass of the whole hydrogen atom... damn it. So really, no matter what you do, it's hard to define units that are completely "fundamental." So might as well just make them in terms of stuff that humans can understand, like feet, stones, and most importantly, imperial pints.
-CausticPuppy "Of all the people I know, you're certainly one of them." -Somebody I don't know