[time-nuts] Question re neutrinos and GPS

Magnus Danielson magnus at rubidium.dyndns.org
Sun Jan 8 18:18:28 UTC 2012


Hi Bill,

On 01/08/2012 06:55 PM, Bill Hawkins wrote:
> Tom,
>
> I had to look up "traveling clock synchronization" to get a
> better understanding, and found this link:
>
> http://www.newtonphysics.on.ca/einstein/chapter9.html
>
> The idea that Qz (time on the quartz clock, no?) drops out in
> the subtraction seems to me to require Qz to be invariant.
> That seems beyond the capability of quartz at the required
> error of one microsecond during the many hours that it will
> take to transport Q between CERN and LNGS. Plenty of time
> for cracks to propagate or chips fall off.
>
> Why do you say we can ignore such effects?
>
> Thanks for any enlightenment.

During the expected 12 hour drive the systematic effects and random 
noise needs to be well contained, to reach the target of below 10 ns 
effect. This calls for metrology grade cesiums or even hydrogen clocks.

We assume it does drift in phase, and that drift if indeed a concern in 
order to achieve the goal.

A stop on the way to compare clocks is being considered.

Cheers,
Magnus




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