In article <4B8A8D21.4030506@ntp.org>,
Danny Mayer writes:
>The reason that they have to apply general relativistic corrections is
>that their clocks are far more precise than anything that even a cesium
>clock will give you. Their current uncertainty is about 5 x 10-16 with
>the NIST-F1 clock. There's a discussion here:
>http://tf.nist.gov/cesium/fountain.htm about their current clock though
>for some reason I don't see any discussion about the relativistic
>corrections for not being at sea level. That memory may have been from a
>discussion I had with Judah.
Cesium clocks are good enough to measure the time shift due
to 5000 feet of elevation if you are willing to wait a couple
of days.
http://leapsecond.com/great2005/
Project GREAT: General Relativity Einstein/Essen Anniversary Test
Clocks, Kids, and General Relativity on Mt Rainier
[Time sink warning.]
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These are my opinions, not necessarily my employer's. I hate spam.
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