Re: Avogadro's shrinking?

[David Scherer <scherer@uiuc.edu>]

Is Avagadro's constant shrinking?  It all depends on where you get you data.
Maybe it is oscillating.  The latest number is slightly higher.

NIST sponsors the Committee on Data for Science and Technilogy (CODATA),
which estimates physical constants by performing least square fits.
Remember that many of the constants are interrelated and adjusting one sends
ripples through the system.  According to the NIST physics department's Web
page, the current recommended list is from 1986.  The previous revision was
in 1973.  The results don't appear to have a downward secular trend:

1973  6.022 045 (31) E23
1986  6.022 136 7 (36) E23

The numbers in parentheses represent the 1 std. dev. uncertainty.

BTW, in case you want to bookmark the Web page for the fundamental constants
(and they have a lot of them), the URL is
http://physics.nist.gov/PhysRefData/codata86/codata86.html

Regards,
Dave Scherer
scherer@uiuc.edu