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That is a rather absurd argument. Consider that the linewidth of the
cesium hyperfine resonance ranges from 1 to 10 Hz, depending on the
atomic beam or fountain configuration, interrogation time, and other
details of clock construction. By your argument, it should be
impossible for even the best cesium clocks to hold time to better than
about 1 part in 9192631770, or 9 microseconds per day. In reality,
the 5071A (a portable cesium beam clock) exhibits an accuracy of
±5×10^−13 and a stability of 2.7×10^−14 over 100,000 s, while cesium
fountain clocks exhibit accuracy and stability in the 10^-16 range.
Are cesium clocks FAKE???
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>
Don't forget that 9,192,631,770 Hz IS A CONVENTION, not a constant of
nature. It has intrinsic (and random) noise of about +/- 2.5 Hz, which
traduces into an uncertainty of about 10E-10.
>
Don't confuse Cs133 frequency shift with the shift of the MASTER TCXO
(5 or 10 Mhz), which is THE HEART of the atomic clock, stabilized much
more through negative feedback. This is the clock used for timing, not
the Cs133, which is used as MASTER STABILIZER.
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