GPS and Relativity

[MacM]

Hi, I'm new here and this is my first post. I hope to get started off on a good foot and not step on any toes.

I was invited here by Dr Strangelove but I tried posting that in my application and it didn't accept his real name, I guess you wanted user names.

Thanks in any case to Dr Strangelove for the invite.

I would like to post my favorite question to any here that may have a qualified different view.

GPS uses the earth's pole as a local preferred rest frame.

GPS satellites have a velocity (V1) of 3,874.5 m/s relative to that frame. A surface clock (V2) at the equator has an absolute velocity to the pole of 463.8 m/s.

The "Relative Velocity" between the orbiting clock and a clock at the equator is V3 = (V1 - V2) = (3,874.5m/s - 463.8m/s) = 3,410.7m/s.

Using SRT Relative Velocity in GPS one gets: 3,410.7/c = 1.1369E-5, squared = 1.2925E-10. Divided by 2 = 6.4627E-11.

Time loss would be 6.4627E-11 * 24 * 3,600 = 5.58378E-6 or - 5.58 micro-seconds per day.

HOWEVER: Using the absolute velocity of orbit V1 = 3,874.5 m/s and NOT "Relative Velocity" per SRT one gets 1.2915E-5c, squared = 1.66797E-10. Divided by 2 = 8.33986E-11.

8.33986E-11 * 24 * 3,600 = 7.205E-6 or 7.2 micro-seconds per day due to orbit velocity.

For the earth surface clock I calculate V2 = 463.8 m/s = 1.546E-6c. Squared = 3.29E-12. Divided by 2 = 1.195058E-12 * 24 * 3,600 = 1.0325E-7 or -0.10325 Micro-seconds per day being only about 1% in the daily time loss may be disregarded.

Over a dozen considerations are made in the GPS system but prelaunch adjusments of GPS orbiting clocks consist of only two primary ones.

About +45 micro-seconds gain due to GR (Gravity) and for a -7.2 micro-second loss due to velocity, for a net adjustment of -38 micro-seconds.

Since it is known that GPS clocks are preadjusted for 7.2 microseconds loss per day (which matches absolute velocity of orbit and not SRT's Relative Velocity as Relativists would have you believe), GPS does not use SRT. It uses the Lorentz Relativity concept of absolute velocities and not SRT Relative velocity. The other adjusments are generally made by software based on signal data.

Further since the velocites and calculations are based on absolute velocities relative to a common preferred rest frame the two components are not reversable as they are in SRT where each can claim to be at rest. In this format the orbiting clock ALWAYS has higher velocity and ALWAYS is the clock which shows dilation.

It is what in fact we observe in reality and the theory of SRT seems invalidated.

BTW: I seem unable to post my Avatar. Is that feature working yet?

[Dr_Strangelove]

The center of the earth is taken to be "the reference frame" because it is more inertial then the surface at the equator. An object at the equator is in constant acceleration (traveling in a circle) , as are the satellites. The center of the earth (or axis) is not truly inertial since the earth revolves around the Sun., however the acceleration from this effect is less and is ignored in the calculations.

[MacM]

The center of the earth is taken to be "the reference frame" because it is more inertial then the surface at the equator. An object at the equator is in constant acceleration (traveling in a circle) , as are the satellites. The center of the earth (or axis) is not truly inertial since the earth revolves around the Sun., however the acceleration from this effect is less and is ignored in the calculations.

I fully agree but my issue is with those that take GPS and claim it proves SRT. It actually only proves Gamma and conviently ignore the whole of the theory of SRT regarding reciprocity (either observer can be considered at rest).

That part of SRT appears totally false.

[Dr_Strangelove]

I too am troubled by the whole "reciprocity" idea. People use it when convenient and discard it when it gets in the way.

In my space/time geometry everything travels through space/time, not space in time. Evaluating the twin paradox, with my space/time geometry, you will see that the traveling twin must breach a space/time “gap” in order to return. He does this during acceleration. I haven’t worked out the details, but I suspect that the traveler would return at exactly the same age as the “stationary” twin. The Sagnac effect provides evidence in support of this.

[MacM]

I too am troubled by the whole "reciprocity" idea. People use it when convenient and discard it when it gets in the way.

In my space/time geometry everything travels through space/time, not space in time. Evaluating the twin paradox, with my space/time geometry, you will see that the traveling twin must breach a space/time “gap” in order to return. He does this during acceleration. I haven’t worked out the details, but I suspect that the traveler would return at exactly the same age as the “stationary” twin. The Sagnac effect provides evidence in support of this.

I think we are very much in agreement. I have further concluded that what current physics calls "time dilation" is a mis-nomer and should be referred to as "clock dilation". that is we are seeing change in measurement as different frequencies being applied to the underlying time interval and no actual affect on time perse.

One consideration is to take an atomic clock (AC) and a pendulum grandfather clock (GFC), claibrate and synchronize them in LA, Calf, then move them to Denver Colorado.

According to Reltivity one speeds up the other slows down. No clocks actually measures time but only mark time at a given frequency as a function of its internal process energy.