The GPS relies on a neo-lorentzian theory of relative motion which assumes, incorporates, and employs the notion of absolute simultaneity. It rejects the relative simultaneity posited by SR.

This claim is easily understood and demonstrated by anyone who understands the difference. The following is an excerpt from a relatively recent article published in the "Journal of Astrophysics & Aerospace Technology:"

In relativity theory there are two versions of time dilation: symmetric and asymmetric. In the first case, it is assumed that a moving clock always runs slower than the observer's local clock, so it is just a matter of perspective which of two clocks runs faster. By contrast, asymmetric time dilation assumes that if two clocks are running at different rates, one of them is unambiguously slower.

The latter view incorporates absolute simultaneity, the former view is propounded by SR. Put another way, the question is "Is time dilation reciprocal (SR) or directional (LR)?" To continue from the article:

The Lorentz transformation (LT) of Einstein's special theory of relativity (STR) predicts that only symmetric time dilation occurs in nature. However, experimental studies of the rates of atomic clocks on airplanes, as well as of the second-order Doppler effect using high-speed rotors, find that time dilation is exclusively asymmetric,** in clear contradiction to the LT [used by SR].**

The form of the LT is identical in both LR (lorentizian relativity, which posits a preferred frame), and SR, but the interpretation (substance) differs. The v (for velocity) of SR is relative whereas for LR it is absolute.

In the present work, it is shown that there is another space-time transformation that also satisfies Einstein's two postulates of relativity, but one which assumes that clock rates in different rest frames are strictly proportional to one another. It is therefore in complete agreement with the results of the above time-dilation experiments and also with the clock-rate adjustment procedure applied to satellite clocks in the methodology of the Global Positioning System; hence the designation GPS-LT for this alternative space-time transformation. **Unlike the original LT, the GPS-LT is consistent with the absolute remote simultaneity of events, and it eliminates the necessity of assuming that space and time are inextricably mixed.**

Think about that. Does anybody actually care about empirical facts? Or is what one has adopted as accepted dogma to be strictly adhered to in the face of any and all evidence to the contrary?

although the LT satisfies both of the relativity postulates, **it fails to predict the results of a number of experiments that were carried out in the latter half of the 20th century. **Evaluation of these experimental results, which were not available to Einstein at the time of his landmark paper, allows for a more precise statement of the physical requirements that must be satisfied in order to obtain a completely satisfactory theory of motion in the absence of gravitational fields. The technology of the Global Positioning System (GPS), particularly the manner in which it makes use of atomic clocks in obtaining accurate estimates of distances on the earthâ€™s surface, will prove to be a key element in the following discussion.

https://www.omicsonl...5.php?aid=55849

The author here is not some rogue, heretical physicist. The points he makes are accepted by mainstream physics (since they are correct). I have summarized and explained these points in this forum numerous times, but as far as I can tell, until recently, not a single poster here understands the issues.

I find it frustrating that such simple, self-evident concepts are so routinely rejected by those pretending to be knowledgeable and informed.

The conception of reciprocal time dilation propounded by SR is prima facie self-refuting and I am amazed that so many can't (or won't) acknowledge that obvious observation.

As any physicist (or any other rational person) will readily admit, it is logically impossible for each of two clocks to run slower than the other.

Those who do not see this as intuitively obvious need only look at the Hafele-Keating experiment, conducted about 50 years ago, for empirical confirmation of this logical necessity. Or to the GPS, which confirms directional (not reciprocal) time dilation thousands of times every day.

**Edited by Moronium, 22 January 2019 - 12:03 PM.**