Pat, The fact you miss is that in "Scientific Metrology" there is no such thing as "exactly the same" for the experimental comparison (calibrations) of two or more *measurements* of any physical quantity (mass in particular). There is *always* uncertainty in measured values of quantities. There can be *no uncertainty* only in *numerical* definitions. e.g. one inch = 25.4 mm exactly.
At the same time, there is no doubt that the CIPM is attempting to make the "new definitions" of the SI Base Units (to be based on numerical values of certain fundamental constants ) as nearly as humanly possible to be compatible with (identical to?) the older definitions based on platinum-irridium artifacts. Gene. ---- Original message ---- >Date: Sun, 20 Feb 2011 18:18:44 +1100 >From: Pat Naughtin <[email protected]> >Subject: [USMA:49890] Re: New BIPM web page on the "New SI" >To: "U.S. Metric Association" <[email protected]> >,,, > Dear Jim, > , I have a concern. > ...From these, it is not clear to me what the mass of > the "new" kilogram is intended to be. Will it be the > same as the mass of the kilogram as it was in 1799 > and 1887? Will it match the current mass of the > kilogram? Orwill it have some other value? ...
