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Can GPS find variations in Planck's constant?

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Can GPS find variations in Planck's constant?
> http://physicsworld.com/cws/article/news/2012/mar/28/can-gps-find-variations-in-plancks-constant

> Physicists in the US say that they have used publicly available data
> from global positioning system (GPS) satellites to put a limit on how
> much Planck's constant might vary from place to place. Their
> technique involves analysing the tiny corrections that are applied to
> the atomic clocks used in GPS satellites – corrections that are made
> to account for relativistic effects caused by the orbits of the
> satellites. However, not all physicists agree that the analysis is
> meaningful.

> GPS relies on extremely accurate measurements of how long it takes
> signals to travel from several satellites to a receiver on the
> ground. As these timings have to be incredibly precise, atomic clocks
> are used on board the satellites. These clocks measure the frequency
> of electromagnetic radiation involved in a specific atomic
> transition, which is related to its energy via Planck's constant.

> For reasons outlined in Einstein's special and general theories of
> relativity, the clocks in space must be corrected on a regular basis
> so that they agree with atomic clocks on Earth and with each other.
> Once the appropriate relativistic corrections are made, however, the
> time on the clocks should be identical regardless of any differences
> in the local gravitational potentials of the clocks. So if there is
> still a deviation once relativity is taken into account, Planck's
> constant might vary from place to place – in other words, the concept
> known as local Planck invariance (LPI) might not hold true.


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Can GPS find variations in Planck's constant? Sam Wormley <swormley1@gmail.com> - 2015-07-25 20:12 -0600
  Re: Can GPS find variations in Planck's constant? alber <invelid@invalid.com> - 2015-07-25 23:58 -0500
  Re: Can GPS find variations in Planck's constant? Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2015-07-26 01:32 -0400
    Re: Can GPS find variations in Planck's constant? "Y.Porat" <y.y.porat@gmail.com> - 2015-07-26 00:21 -0700
      Re: Can GPS find variations in Planck's constant? "Mort Friedman" <invalid@example.com> - 2015-07-26 13:31 -0700
        Re: Can GPS find variations in Planck's constant? Lofty Goat <rlwatkins@gmail.com> - 2015-07-26 23:56 -0500

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