Thursday, October 1, 2009

Satellite GPS and Atomic Clock Confirm Relatvity?

Do satellites really confirm Relativity? This "fact" is usually touted as the big thing that pretty much proves the gravity hypothesis of the universe. Not so fast. Here is a good analysis:

GPS AND RELATIVITY: AN ENGINEERING OVERVIEW
Henry F. Fliegel and Raymond S. DiEsposti
GPS Joint Program Office
The Aerospace Corporation
El Segundo, California 09245, USA

Conclusion (from the paper):

Except for the leading [gamma] factor, it is the same as the formula derived in classical physics for the signal travel time from the GPS satellite to the ground station. As we have shown, introducing the [gamma] factor makes a change of only 2 or 3 millimeters to the classical result. In short, there are no "missing relativity terms." They cancel out.

An alternative hypothesis to why atomic clock rates change and additional analysis of relativity and GPS:


Rethinking Relativity
Tom Blethel




2 comments:

  1. If that's true, then how is it that the satellites that were put into orbit with a relativistic frequency correction *work*? They should be outputting at the wrong frequency, and thus be non-functional, no?

    ReplyDelete
  2. The 1995 Fliegel and DeEsposti paper has since been showed flawed. Further - and what you're getting at Brian - is that GPS includes these corrections and works, and you can get further info on the corrections. For more info, see:

    Subsequent paper on relativistic effects and GPS, referencing the above paper:
    http://www.pttimeeting.org/archivemeetings/1997papers/Vol%2029_08.pdf

    Technical details of corrections and experiments:
    http://relativity.livingreviews.org/Articles/lrr-2003-1/

    GPS implementation related document, including relativistic effects:
    http://www.navcen.uscg.gov/GPS/geninfo/IS-GPS-200D.pdf

    And more generally:
    http://dealingwithcreationisminastronomy.blogspot.com/2009/04/scott-rebuttal-i-gps-relativity.html

    ReplyDelete