[time-nuts] Optical link connects atomic clocks over 1400 km of fibre

[Poul-Henning Kamp]

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In message <1057836989.2088307.1472104857885.JavaMail.yahoo at mail.yahoo.com>, Br
uce Griffiths writes:

>You'd need a rather thick copper jacket to shield effectively
>against the 50Hz magnetic field.

As in: A good-sized fraction of the wavelength if I recall :-)

Electric fields are so much easier...

One interesting thing here is that across distances like this,
there would be significant longitudal currents in such a shield.

Not as bad as metal spanning the Mississippi, but getting there.


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