[LEAPSECS] Schedule for success

Jonathan E. Hardis jhardis at tcs.wap.org
Tue Dec 30 23:25:14 EST 2008



>The NIST web pages also make the wikipedia-cited claim that the ITU

>chose the apellation "UTC".

>

>http://tf.nist.gov/general/misc.htm#Anchor-14550

>

>I can find no evidence to support this, and much evidence to refute

>it. Perhaps the evidence is buried in one of the private documents

>shelved in Geneva...


Steve,

We're talking about a technical decision made in 1970, not 1790.
Many of the people involved then are still around, active in the
field. If this story were not true, don't you think that SOMEONE
would have spoken up about it by now?

'Fess up. Do you think the moon landing the year earlier (1969) also
lacks evidence to support it?


>I find those NIST statements to be about as accurate as the NIST

>press release this month which indicates that their

>less-stable-than-quartz-crystal ammonia molecule clock was the first

>atomic clock.


I'm not entirely sure what you're fussing about. That ammonia is a
molecule and not an atom? That the first clock system based on
discrete quantum states turned out to be not as good as cesium would
ultimately be?

I have no problem referring to it as an "atomic" clock since all the
action is in the nitrogen atom, which moves back and forth between
the two minima of its double-well (at least in superpositions of such
states). I remind you that Charles Townes built his first maser --
an ammonia maser -- in 1954. It was a nice prototype system of its
day.

- Jonathan


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