[time-nuts] ARRL FMT results

[M. Warner Losh]

In message: <20070104.141507.-1417618977.cfmd at bredband.net>
            Magnus Danielson <cfmd at bredband.net> writes:
: From: "Poul-Henning Kamp" <phk at phk.freebsd.dk>
: Subject: Re: [time-nuts] ARRL FMT results
: Date: Thu, 04 Jan 2007 12:05:54 +0000
: Message-ID: <33566.1167912354 at critter.freebsd.dk>
: 
: > In message <20070104.044145.1474621952.imp at bsdimp.com>, "M. Warner Losh" writes
: > :
: > >I have a silly question about these measurements...
: > >
: > >Since the signal is being transmitted from a fixed point.  Wouldn't
: > >people west of the transmitter measure a different (lower?) frequency
: > >than those east of the transmitter due to the rotation of the earth?
: > >Or are those effect well below the margin of error that people have
: > >reported measuring?
: > 
: > 
: > You're a couple of hundred years behind on physics Warner :-)
: > 
: > Speed of light is constant, so as long as transmitter and receiver
: > does not move relative to each other, the frequency stays the same.
: > 
: > But there will be a correction for their relative height in the
: > gravity field (as shown by Toms mountain excursion).
: 
: However, if the signal "bounces" on an "object" moving towards or from the
: receiver there will be a doppler effect. This is used in radar for instance.

But there's a finite amount of time between when the signal is
transmitted and when it is received.  During this time, the earth
rotates, thus bringing the receiver either closer to or farther away
from the transmitter.  Doesn't that cause a frequency shift?  Isn't
this the Sagniac effect?  Small, but measurable as it is a
relativistic effect, no?

Warner