Sujet : Re: Perfect clocks
De : tjoberts137 (at) *nospam* sbcglobal.net (Tom Roberts)
Groupes : sci.physics.relativityDate : 04. May 2024, 16:46:19
Autres entêtes
Message-ID : <UJOcnYVbrZnWxav7nZ2dnZfqlJ-dnZ2d@giganews.com>
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On 5/1/24 12:06 PM, Maciej Wozniak wrote:
sane people, as anyone can check at GPS, keep assuming the second to be 9 192 631 770 on Earth,
This is not an "assumption", this is the definition of the second --
that's what these words mean.
but 9 192 631 774 on a GPS satellite.
This is not true. NOBODY thinks that (except some deranged idiots around
here).
On a GPS satellite, the usual definition of the second applies. But in
order for the SIGNALS from GPS satellites to be received on earth at the
correct frequencies, the time-base on the satellite must tick about 4
parts in 10^10 more slowly than a corresponding time-base on earth's
geoid (mean sea level).
It turns out that the correction to the satellite time-base to cancel
the blueshift of the signals is also the correction required to keep the
satellite clocks in sync with standard clocks on earth's geoid, over
long periods of time (days to years). So the indicated time of satellite
clocks advances with this (slightly slower) time-base. This is not
happenstance, and is a check on the internal consistency of General
Relativity.
Wozniak should stop making stuff up and pretending it is true -- that's
useless.
Tom Roberts