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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."

15 of 315 comments (clear)

  1. The correct measuring scale by Anonymous Coward · · Score: 3, Interesting

    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.

    1. Re:The correct measuring scale by lightspawn · · Score: 2, Interesting

      1 length - the distance across 1 hydrogen atom

      1 time unit - the time required for a hydrogen nucleus to vibrate once


      Are these values completely constant? Whenever somebody tried to convince me that something is always constant, turned out it wasn't.

      Are you sure these values haven't changed since the creation of the universe and will not change in the future?

      Also: What happens when you can measure these values more accurately? Suddenly all your old measurements are wrong.

    2. Re:The correct measuring scale by CarlDenny · · Score: 3, Interesting

      Umm, no.
      Those are some fairly difficult to measure constants you've got there, and almost assuredly not enough to actually use as the basis of a measuring system. They are also almost as bad as say basing temperature on the boiling points of water.

      The "basic" units needed:
      Time
      Length
      Mass
      Charge

      With one more point thrown in for good measure:
      The zero of the temperature scale.

      Absolute zero is a very well defined place by the laws of statistical mechanics, and clearly should be left exactly where it is.

      The unit of charge should be the charge on a down quark. (1/3 e)

      The basic units of time, length, and mass should be chosen so that G,c, and hBar = 1. Those are the constant of universal gravitation, the speed of light, and Planck's constant (a constant from quantum mechanics related to wave/particle duality.)

      All the other units fall out from these:
      unit energy = (unit mass)(unit length)^2/(unit time)^2
      temperature degree = 1/(unit energy) ...

  2. Sigh. by Guspaz · · Score: 5, Interesting

    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!

  3. Not that big a deal by helix400 · · Score: 5, Interesting
    It was nearly impossible to design a system that wasn't arbitrary.

    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.

    1. Re:Not that big a deal by Tintivilus · · Score: 2, Interesting

      Actually, the kilogram is no longer officially defined by the alloy sample (at least according to my phys prof). it's based on the molar mass of C12 -- a gram is defined as 1/12 the mass of 6.0220245x10^23 atoms of Carbon-12.

      Of course, that number of atoms (Avogodro's Number) was originally defined as "the number of atoms in a 12-gram sample of C12" so it's still perfectly arbitrary. Gotta love circular definitions :).

      Don't forget Mole day on June 2nd (6.02)

  4. Re:Arbitrary doesn't matter... by Anonymous Coward · · Score: 1, Interesting
    It's abitrary for humans except for time, where any unit will have to be based around most people's circadian rythms, the duration of a day, and the duration of a trip around the sun.

    Even if we left this planet we'll still have that kind of thing built in to us.

  5. A Brit pipes up... by The_Guv'na · · Score: 2, Interesting


    I remeber the furore over the conversion to the metric system well. I was working and the lowest crappiest most poorly managed lame-arse crumbling sorry fucking excuse for a cheapo shit-hole supermarket at the time.

    I prefer the metric system, it makes sense, in ways already mentioned here. What I do not agree with, is our Government forcing shops to sell stuff in metric units, and fining retailers for selling stuff in imperial units...

    What the fuck? Nobody is getting ripped off, the supply chain all the way to the shop shelf is metric, but the customers are forced to buy stuff measured in metric units; does it matter? NO! My rant is about the government fining and jailing private traders who sell in imperial measures. They are just pleasing customers! And metric units are always there to be used if desired.

    When I worked at a timber yard, long after the metrication debacle, most customers still used imperial measures. They were brought up on them, simple as that. Thus, 8foot X 4foot shhets became 1220x2440mm sheets, and 10feet became 3050mm. Great for mental arithmetic exercise.

    They could have educated people about both systems, and let people choose. Within a few decades the imperial system could be done away with quite easily. But no, it has to be shoved down our throaghts in almost no time at all!

    I'm only 20 and I remember the metric system being taught at school: Cubits, digits, palms, etc...

    Ali

  6. Re:Why? by Crazy+Ukrainian · · Score: 2, Interesting

    So just because it is "a major undertaking to convert" we shouldn't do it? Are we to keep saying that just because its too much work it shouldn't be done at all? I know most of use here are lazy, but come on, it doesn't all have to be done at once. Start in the brainwashing facilities the US calls schools, and work your way up. And the imperial system IS less usefull. Like you said, it can be annoying to work with, and since most of the world uses metric, it makes unit communication a pain too. Just convert and be done with it.

  7. Re:Why? by metalpet · · Score: 5, Interesting

    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.

  8. Wavelength of hydrogen. Binary. by texchanchan · · Score: 3, Interesting
    Wavelength of hydrogen equals approximately 21 centimeters, a handy (literally, eh?) size for us humans.

    Multiplied by 2, divided by 2.

    I'll stake my cat this is in use already.

    ...Just not here.

  9. Re:Who cares? by iggymanz · · Score: 2, Interesting

    Is there a cult of metric haters that I'm not aware of?

    yes, the inhabitants of the U.S. of A. I remember being taught the metric system (but the non-ISO version with centimeters and liters) in the 70's, because we'd (we as in U.S.A) would all be using it by 1980. But we stubbornly stick to the length of the kings thumb on extended arm to his nose for length (gerd....now pronounced yard) and work a horse could do in 1 second, etc.etc..

  10. Arbitrary...this is news? by Random+Addict · · Score: 2, Interesting

    Look, any measuring system is going to be arbitrary. This is because the concepts of number and measurement are human concepts invented by the human mind. They have no objective source in nature. They are simply ideas that the human mind uses to understand the world around us. Mathematics is not a science, it cannot be, since it has no subject matter. All any mathematical system can do is manipulate numbers. And numbers have no existence outside the human mind. The fact that humans cannot understand the universe without resorting to number and measurement just points out the limitations of the human mind.

    --
    __
    The optimist proclaims we live in the best of all possible worlds. The pessimist fears this may be true.
  11. That won't work for temperature by CausticPuppy · · Score: 3, Interesting

    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
  12. balanced ternary by spdegabrielle · · Score: 2, Interesting
    This article in American scientst suggests balanced ternary as a good option for counting systems. It includes negative numbers and makes giving change easy.
    Too weird? Perhaps.

    The Article also gives the following quote;

    "Perhaps the prettiest number system of all," writes Donald E. Knuth in The Art of Computer Programming, "is the balanced ternary notation."