The Past, Present and Future of Measurement
Lengthy but interesting post about forthcoming changes to the definition of four of the base units of the SI system.
Measurement, the simple process of comparing an unknown quantity with a standard quantity, is the essential component of all scientific endeavours. We are currently about to enter a new epoch of metrology, one which will permit the breath-taking progress of the last hundred years to continue unimpeded into the next century and beyond.
The dawn of this new age has been heralded this week by the publication of an apparently innocuous paper in the journal Metrologia. The paper is entitled:
Data and Analysis for the CODATA 2017 Special Fundamental Constants Adjustment
and its authors, Peter Mohr, David Newell, Barry Taylor and Eite Tiesinga constitute the Committee on Data for Science and Technology, commonly referred to as CODATA. In this article I will try to explain the relevance of CODATA’s paper to developments in the science of metrology.
The Past
The way human beings began to make sense…
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October 23, 2017 at 9:10 am
In line with the new definitions of mole and ampere, why not just define the kilogram as the mass of a certain number of moles of a certain substance? I think that this was one of the proposals. Why did it lose out?
October 23, 2017 at 7:20 pm
A kilogram is quite a large quantity and the temperature is a problem.
October 24, 2017 at 7:55 am
Is that why this proposal (which IIRC was one of at least two competing proposals) lost?