From the Wall Street Journal – By JEANNE WHALEN
In a vault beneath a 17th-century pavilion on the outskirts of Paris sits a platinum cylinder known as Le Grand K. Since 1889 it has been the international prototype for the kilogram, the standard against which all other kilos are measured.
But over the years, scientists have noticed a problem: Le Grand K has been losing weight. Weigh-ins at the International Bureau of Weights and Measures show that the bar has shed approximately 50 micrograms—roughly equal to a grain of sand.
The problem has vexed scientists who monitor the kilo the way tabloids track the waistlines of Valerie Bertinelli and Kirstie Alley. The stakes, however, are weightier.
“It’s a scandal that we’ve got this kilogram hanging around changing its mass and therefore changing the mass of everything else in the universe!” Bill Phillips, a Nobel Prize winning physicist, exclaimed at a scientific summit in London this week. No one knows for sure what went wrong with Le Grand K, but some theorize it lost weight from being cleaned.
Dr. Phillips and other mandarins of metrology were gathered at Britain’s Royal Society to debate an urgent question in the science of measurement—how to re-define the basic unit of mass, as well as other measurements such as the second, ampere, kelvin and mole.
The aim is to tie each to a widely accepted property of nature, rather than to a lump of metal or some other imprecise benchmark. The meter, for instance, was once measured as the distance between two notches on a metal bar. It is now defined as the distance light travels in a vacuum in 1/299,792,458 of a second.
The new definitions are “as big a change as the introduction of the metric system during the French Revolution,” says Terry Quinn, a dapper Briton who organized the seminar and once served as director of the International Bureau of Weights and Measures, which ensures world-wide uniformity of measurements. Frequent clashes about the best approach mean the temperature of debate has at times “risen quite high,” he added, without specifying by how much.
Full story at the Wall Street Journal
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I have yet to meet an American who can tell me
1) how many feet to a mile
2) how many square-feet to an acre
3) what a pound is, and what is measured by it
4) how many Watts in a horsepower
5) the unit one measures blood pressure in
All very simple if you know metric.
But when it is important, even Americans go decimal: A $ has 100 cents, not 64.
Since the masses are only compared every 50 years (from OzWizard’s comment) has the technology changed in how they do this measurement. It would not be impossible to me that the difference in mass is due to knowing the relative values better than 50 years ago.
If I remember correctly they do take many measurements and use the average value to get a more precise measurement. How precise are the measurements? 50 micrograms seems like a really big error. My 100 gram standard weight is rated to 10 micrograms.
Converting feet to meters…
http://www.climb.mountains.com/Word_Tent_files/Feet_to_Meters.jpg
metric confusion…
http://articles.cnn.com/1999-09-30/tech/9909_30_mars.metric_1_mars-orbiter-climate-orbiter-spacecraft-team?_s=PM:TECH
Looks like light is used to describe two physical thingies, the meter and the second.
Have the scientists taken into consideration, the speed of the Earth, in the galaxy, and the speed of the galaxy in the universe?
Earle Williams says:
January 29, 2011 at 9:47 am
johanna,
I noticed that same thing about Australians and their height about 25 years ago. I was a student intern at Argonne laboratory and there was a gent from NSW there. During an evening of beer consumption and lengthy coaching on the proper way to pronounce the word ‘bastard’, the issue came up of Americans’ reluctance to embrace the metric system. After putting up with a fair amount of good natured ribbing I ask Ken how tall he was. His reply? “5 foot 11, you bastard.”
—————————————————————–
Earle, if he called you that, you were undoubtedly classified as a friend, or mate. The term ‘bastard’ in Australia is often affectionate, and no-one connects it to its original meaning of not knowing, or being acknowledged by, one’s father any more.
Interesting to read posts from people who are ‘bi-lingual’ in metric and other measures. That is how it is in Australia, despite decades of metrics. As I suggested earlier, perhaps we need a metric equivalent to the inch and foot.
Measurement nerds, arise! The steamrolling of your knowledge in discussions about weather and climate has gone on for too long.
I couldn’t resist a cartoonish view:
http://polistrasmill.blogspot.com/2011/01/metrology-notes.html
Stupid newsies! Don’t they check to see if they have run this story before? This is old, old news. News stories about an inconstant kilogram have appeared off and on since 1990. They pop up often enough that the BIPM (the organization that keeps the international kilogram prototype in a basement of a castle outside Paris) have a FAQ entry on it: http://www.bipm.org/en/scientific/mass/faqs2_mass.html.
As others have noted, there are a number of competing approaches to eliminate the need for that prototype. It would be extremely nice to do so; the kilogram is the last of the basic units whose definition still relies on a prototype. However, the replacement will have to (a) be as accurate as the prototype-based approach, (b) based on extremely solid science, (c) verifiable, and (d) replicable. So far, no joy, but there has been a lot of progress as of late.
Well at least we got a good deal on the Louisiana Purchase.
Mass – The rest mass of an electron,
Distance – The diameter of a helium nucleus,
Time – The time it take a photon to cross a helium nucleus,
etc
As a civil engineer, I am always concerned about that thing called praticality and potential for error, as well as usefulness.
Our use of stations (100 feet) and a decimal foot for measurement of length was wonderfully practical. Say 20+75.27 for 275.27 feet, or 2300+27.75 for 2327.75 feet. People are prone to make errors in transposition with long strings of characters. Misplacing the decimal point left or right one place with long strings of numerical characters became too common when digital calculators became common, making a result off by a factor of 10.
With the metric system, the units are either too large or too small to be of practical use for civil engineering, in my humble opinion. I have used both, as a civil engineer.
As I majored in physics back in the late 1950s (2 semesters first as a pre-engineering student, 1953-1954), I am familiar with the three systems, centimeter -gram-second (cgs), meter-kilogram-second (MKS) and foot-slug-second, used then.
The right tool for the job at hand works well indeed.
When dealing with very small units, the metric system works very well, as values can be expressed with short, whole numbers, as well as with very large units.
Gravitygate. I have been told that the universe is expanding at an increasing rate; I believe that as surely as I believe that the weight of the standard kilogramme has been declining, (whether or not it is true). It is therefore obvious to the meanest intelligence that gravity is a repulsive force, and that that force holds bodies like the earth and sun together, and gives masses on the earth their weight. As the universe expands, not only will the earth expand slightly but the weight of masses on its surface will decline. That has the advantage that, like H G Wells’s Pycraft, as I lose weight without losing mass, the strain on my heart is decreasing and I might live a microsecond or two longer.
I have complete faith in this account, as I have faith that the universe was created in six days and is a jolly good thing, and as I have faith that AGW is true. I do not accept that I ought to listen to others just because they know much more physics than I do. Why should I? Faith avoids the onerous requirement that we reason. Please note that I have seen no need to generate computer models to prove my point – which is fortunate given my computing ability.
It is plain that there is a conspiracy, which I call Gravitygate, to prevent the truth about gravity being noised abroad. I cannot believe that many others do not know the truth. Surely they do not fear looking stupid if they own up.
Metrology is a problem between the US and Europe especially. We have all sorts of screw threads since Whitworth, but probably the most enduring standard is BSP, the British Standard pipe thread, although one needs a fair bit of knowledge to understand those threads (1/8″ BSP is very roughly equivalent to 1 cm in diameter, e.g., hence a wee bit illogical).
The USA followed UK screw thread manufacture fairly closely, until they decided to make their own. The nut (bolt head) sizes may be the same, so you can use your “standard” a/f (across flats) socket set, but the screw threads may not now be so.
The Europeans, on the other hand, have ‘screwed’ up things royally with their metric screw threads – not one, but two pitches (fine & coarse), and their own pipe threads, with a slightly different pitch angle.
So, although I am conversant in degrees F to deg C, and vice versa; psi to bar, and vice versa, etc, etc, and all the various ramifications of different units, I am not ever sure of screw threads!
The moral of this little tale is, I suppose, that you should always check your units of measurement. Failure to do so could result in either a very costly plant shut-down, or an explosion.
Vince Causey and Slacko,
2002 – The International Committee for Weights and Measures (CIPM) considers the metre to be a unit of proper length and thus recommends this definition be restricted to “lengths ℓ which are sufficiently short for the effects predicted by general relativity to be negligible with respect to the uncertainties of realisation.”
Wait a minute, I thought the speed of light was an average???? Didn’t someone discover light travel at different speeds at different wave lengths/colors????
The SI definition makes certain assumptions about the laws of physics. For example, they assume that the particle of light, the photon, is massless. If the photon had a small rest mass, the SI definition of the metre would become meaningless because the speed of light would change as a function of its wavelength. They could not just define it to be constant. They would have to fix the definition of the metre by stating which colour of light was being used. Experiments have shown that the mass of the photon must be very small if it is not zero
http://www.phys.ncku.edu.tw/mirrors/physicsfaq/Relativity/SpeedOfLight/speed_of_light.html
So which color did they choose? How about purple, I like purple…
@dscott
The speed of light in vacuum is independent of frequency (color/wavelength): light waves aren’t dispersive. That’s a direct consequence of Maxwell’s equations.
@DesertYote
I guess the metrologists are aiming at a very precise and fundamental definition of the unit of mass. The atomic mass unit (1/12th the mass of a Carbon-12 atom, which is more or less the average mass of a nucleon) is similar to your idea of the rest mass of an electron, but this does not seem to be fundamental enough. Perhaps because the mass of the electron is subject to renormalization due to electromagnetic self-interactions. Also, using nuclear radii to establish a length unit is not enough: even a proton (or electron) has not a well-defined radius, tough it has what is called a “classical radius”. The idea of radius of these entities gets rather fuzzy, once you get down to the quantum level. Finally, many photons would have problems going across a helium nucleus: for instance, a visible photon has a wavelength about four orders of magnitude greater than the average atomic radius.
It seems to me that metrology is terribly subtle.
Mooloo says:
January 29, 2011 at 2:07 am
If the US were persuadable by reason, they would be metric by now. Like the rest of the world.
Now that’s what we Yanks call “doubling down on stupid.”
Or, in metric, “tripling down on stupid.”
Any kind of censorship and ideological persecution leaves a bad aftertaste in my mouth (especially when it is endorsed by the bad-mannered and self-proclaimed “world’s foremost specialist” in anything).
In this regard, I would like to get an explanation of why, exactly, proponents of the certain (however ridiculous) “Electric Universe theory” are silenced here, while proponents of the much more ridiculous creationist “Big Bang theory” are given the green light.
Is it that the Big Bang “consensus” (postulating that 98% of our Universe is a mystical cloaked matter, mysterious divine-like forces operating outside the laws of conservation of mass and energy, and other mythical epicycles and fudge factors that nobody can ever observe — just to fit reality to formulas) is somehow less fraudulent than the AGW “consensus”?
If I don’t understand something here, I would like to be enlightened.
“ktwop says: January 28, 2011 at 8:55 pm
The metre is now the length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second (with or without a gravity field?). A second is no longer connected to the length of a day and its sub-divisions but is now the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom at rest at a temperature of 0 K.”
And have we ever been able to get to 0 K, let alone measure anything?
Lots of great comments!
Whitworth is the right system for what it was developed — steel fasteners.
It has no meaning or rational basis outside of steel fasteners. Similarly the
Morse taper system is great for steel tooling, and only steel tooling. For
their domains, these systems are essentially perfect. (Sticking tapers,
like Morse, need the closure angle tangent to be the coefficient of static
friction of the target material.)
Where Whitworth fails is in ease of manufacture. Relative to the similar
60 degree thread system, Whitworth tooling is at least 10x as hard to make!
Whitworth fails to be useful in aluminum. Thus the US was not interested
in using a difficult-to-tool non-aluminum-compatible system for making
airplanes in emergency mode in WWII.
Do some research, and take a read through “The Measure of All Things”.
The metric system was devised thusly:
1) Choose a random galaxy, in it a random sun, near it a random planet.
2) Make 7 attempts to measure a random section of the planet. Get tired
of trying to measure. Give up and declare the job “done”.
3) Translate the “done” number into some arbitrary numerical base
4) Decide that the number, as represented in that base, is “too big”.
5) Choose a semi-random set of prime numbers, 14 in all.
6) Repeatedly divide “too big” by all these primes until the “just right”
number is found.
7) Choose a random substance on this random planet. Fill a 3-dimensional
box of size “just right”^3 with the substance.
8) Choose a second random substance on the random planet.
9) Try 5 times to make a good copy of the same mass of random substance 1
“just right”^3 in random substance 2. Give up, and declare the result a
standard.
10) Call the result a “standard kilogram”.
11) Celebrate, and declare your standard to be obvious, universal, non-arbitrary,
and very important. Insist on it!
That, my friends, is a true summary of the Metric System. It is no less arbitrary
than the width of my thumb, or the measure from the end of my nose to the end
of my finger.
Whenever proponents of any theory, however ridiculous, are censored out from any forum, I feel bad aftertaste.
Especially if this action is supported by the self-proclaimed “world’s foremost specialist” in something, who himself is a proponent of a much more ridiculous theory called “Big Bang”.
Talk about consensus. Some consensus bad, other consensus good?
“Laurence M. Sheehan, PE says:
January 29, 2011 at 12:47 pm
I am familiar with the three systems, centimeter -gram-second (cgs), meter-kilogram-second (MKS) and foot-slug-second, used then.”
Of course, cgs is now part of MKS, which is now SI.
But what I would like to know: Energy in the foot-slug-second-system must be in pound(force)*foot, power in pound*foot/second, but what are the units used in electricity instead of Volts, Amps etc.?
The universe is returning to the nothingness from whence it came. No big mystery. If the mass loss in that chunk of platinum continues at the current rate it’ll disappear completely in 2 million years.
Re: “Whenever proponents of any theory, however ridiculous, are censored out from any forum, I feel bad aftertaste.”
To some extent, I perhaps have to apologize for being too specific and wordy in my attempt to talk about mass and gravity on this climate blog. In this regard, my post was inappropriate.
That said, I do believe that there must always be a place for discussions of electricity in space in discussions of weather and climate, because the two topics clearly intersect on many very important points. To think that we all spend so much time discussing the weather and climate of the Earth, without using our observations of other planets’ circulation systems in our solar system as a test for these models, I think shows that we are overly-compartmentalizing the climate modeling issues to suit our pre-existing views on climate.
I am very accustomed by now to being the ugly duckling in the forum world. I am extremely familiar with the widespread hostility towards any theory which proposes that electricity in space does things of great importance. The challenge I regularly face is in fitting these arguments into the format which is demanded by related blogs.
In my own personal view, the problem of modern science is increasingly a human problem: We restrict our reading to suit our pre-existing belief systems. And, for whatever reason, the further one climbs the scientific ladder, the less that anyone can force that person to read something which they already disagree with. This is a major problem, as it facilitates the problem with formulating a complete set of inferences for our observations.
I understand that Anthony depends upon a healthy conversation here on these blogs. But, I would also ask everybody to realize that the complaints of conventional theorists and scientists have single-handedly blocked a more widespread dispersion of the Electric Universe arguments for a couple of decades now. The pattern by now is set in stone: Documentaries are always ditched at the point where a third-party scientist is asked to vet the video. It is these behind-the-scenes politics which lend the impression to the public that this debate is something which we can safely dismiss.
And yet, IEEE’s Transactions on Plasma Sciences continues to publish on this subject (IEEE is the world’s largest scientific institution, btw). And those who follow along with my arguments will notice that few of the pressing controversies which I bring up are ever responded to by conventional thinkers. They are generally ignoring them.
After all, we now know that magnetic fields are observed to permeate the largest scales of the universe. In the laboratory, electric currents are the first logical inference for such an observation. But, in space, it is the one inference which is out of bounds and not taken seriously for papers submitted to the Astrophysical Journal.
In the EU view, the Earth’s weather and climate is a product of its heliospheric plasma environment. Water is a dipolar molecule, which means that it is subject to electromagnetic forces. It is also clearly an excellent conductor — which on large scales facilitates the movement of charge between Earth and space. These moving charges can do all sorts of important things. They can, for instance, drag neutral matter, in the process creating wind.
To ignore these things — which by themselves should not be incredibly controversial — we’d be serving an ideology which limits the role of cosmic electricity. I think that some of the readers of WUWT have already reached this point of realization — even if Anthony has not.
The notion that we should all agree on our assumptions — the cosmological framework of the Big Bang, Standard Solar Model, etc. — in our discussions of weather and climate is not based upon any philosophy whatsoever. The cosmology is by definition in fact the weakest portion of our entire system of scientific thought. Surely, we can all agree on this point.
Unless I have overlooked a post, I am shocked that nobody has brought up the bizarre incident of the moon rover robot whose initial problems were alleged to have been caused by some of the engineering being done with the metric system and the rest done in “American”. I don’t know if this was true or not, but it was widely reported at the time and caused NASA a lot of embarrassment.
Unless I have overlooked a post, I am shocked that nobody has brought up the bizarre incident of the moon rover robot whose initial problems were alleged to have been caused by some of the engineering being done with the metric system and the rest done in “American”. I don’t know if this was true or not, but it was widely reported at the time and caused NASA a lot of embarrassment.
http://articles.cnn.com/1999-09-30/tech/9909_30_mars.metric.02_1_climate-orbiter-spacecraft-team-metric-system?_s=PM:TECH
Self referencing in definitions is always going to be a problem. If the kilo reference has changed, the kilo has changed. If the speed of light has changed, the length of a metre has now changed. If the time it takes for an electron to orbit an caesium atom changes, our definition of a second changes.
How is it determined that the references the definitions are based on aren’t themselves changing? In this case it has obviously been noted somehow that there has been a small change in the reference – how?