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RE: SI Units (continuing history)



Re: SI units thread

These discussions have gone in many fields and at times would have
terminated in duels if such were still de rigueur.  Generally, it seems to
take the death of one or more generations before there is reasonable
acceptance of such changes.

One advantage often not mentioned for the SI is ease of understanding
material outside of a narrow specialty.  UV, light, and IR were a mess until
after WWII, especially as they were treated by different disciplines.  Then
there was international agreement to abandon the multitude of strange units
such as the lambert and foot-lambert, stilb, E-viton, einsteins/sec, finsen,
langley, multiple meanings of emittance, ..... ad infinitum.  Only the
footcandle (lm/ft^2)  persists for lighting, doubtlessly due to the
architects who insist on constructing buildings using the English
(inch-pound) unit of length.  Now it is usually possible read articles in
diverse fields such as optics, photobiology, and engineering without a
crib-sheet and a calculator.

Robert E. Levin, Ph.D.
Corporate Scientist
OSRAM SYLVANIA
71 Cherry Hill Drive
Beverly, MA 01915
phone: (978) 750-1594
fax:      (978) 750-1794
e-mail:  robert.levin@sylvania.com   

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