On Mon, 08 Apr 2002 11:30:15 James R. Frysinger wrote: ... > Physical artifacts (objects) change dimension with temperature. One of >the most precise methods of measuring distances (lengths) is >interferometry, which is senstitive to less than one wavelength of >light. An atomic transition is more stable and in the long run much more >precise than a physical meter stick, even one with fussy temperature >controls. > True, and I was already aware of that. I was just merely advocating that we did not abandon the conceptual way of going about defining a fundamental unit of measurement like the meter. A way that would not use the crutch of another fundamental unit, like the second. A definition that could stand by its own, if at all possible.
> Physical standards (artifacts) are also located in only one spot at a >time. Thus, NIST still must have its kilogram mass compared periodically >to the prototype in Sevres. They used to have to do this with their >meter artifact, as well. But now, anyone can set up a valid meter >standard for a relatively small sum and don't have to worry about their >national standard being lost at sea or out of use during calibration. > True, too. It's just unfortunate that our current state of technology hasn't allowed us yet to get rid of the kg artifact. Hopefully they'll be able to do that in the next 10 years or so. >... The CIPM is going for precision >more than public understanding by those without sufficient background >(at least a few years of physics, for example). For an analogy, ask >yourself this: Should modern medicine limit itself to diagnostic, >surgical, and therapeutical techniques that the common man on the street >can understand? Ooops, there go our MRIs, CT scans, laser sugeries, etc. > > Your inclination to stop progress on realization of standards, due to >lack of understanding, is quite analogous to the inclination of >Americans not to commit to the metric system, which they feel they don't >understand as well. The accuracy of those feelings has nothing to do >with their resulting inclinations. An unkind person might say that >you're just being a luddite at a higher level of misunderstanding. Of >course, that's quite blunt and perhaps tactless, so I wouldn't put it >that way. > ? I don't want to misinterpret your post, Jim, but I am this close to resent it! It's unfortunate that you misunderstood my intentions completely. Even though I assume you haven't had the chance to see my recent reply, I'll take this opportunity here to repeat it once again (therefore, please, "read my lips"): I do NOT want to 'stop progress on realization of standards', EVER! My contention is simply that we do this in the confines of rigid scientific methodology, without compromising or jeopardizing certain definitional structuring and concepts. If there is urgency in obtaining an additional decimal digit, fine, provide a *temporary* alternative if available. I could go along with this current definition of the meter until we found something just as good but that would be more in harmony with our SI tenets, that's all. Marcus Is your boss reading your email? ....Probably Keep your messages private by using Lycos Mail. Sign up today at http://mail.lycos.com
