GPS relativity error - really?

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    Error Gps Relativity
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Discussion Overview

The discussion revolves around the role of relativity in the functioning of the Global Positioning System (GPS), specifically addressing claims about the necessity of time dilation corrections to avoid significant positioning errors. Participants explore the implications of gravitational time dilation and the operational mechanics of GPS satellites.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • Some participants argue that the commonly cited 12 km error in GPS positioning due to relativity is misleading, suggesting that GPS can function adequately without constant relativity corrections for short periods.
  • Others contend that GPS satellites' clocks are adjusted for relativistic effects, making further corrections from ground signals smaller and simpler.
  • There is a suggestion that the time dilation experienced by satellites is similar due to their shared orbital altitude, potentially mitigating the need for extensive corrections.
  • Some participants emphasize that the adjustments for relativity are straightforward and necessary for maintaining accuracy in GPS calculations.
  • One participant challenges the validity of the original claim about GPS errors, asking for sources that support the assertion that GPS would fail without relativity corrections.
  • There is a discussion about the accuracy of atomic clocks on satellites and the methods used to ensure correct timekeeping, including frequency modulation techniques.

Areas of Agreement / Disagreement

Participants express differing views on the necessity and impact of relativity corrections in GPS technology. No consensus is reached regarding the validity of the 12 km error claim or the sufficiency of the current GPS system without these corrections.

Contextual Notes

Some participants note that the discussion lacks definitive sources to support claims, and there are unresolved questions about the exact workings of GPS and the implications of time dilation on positioning accuracy.

Who May Find This Useful

This discussion may be of interest to those studying relativity, GPS technology, or the intersection of theoretical physics and practical applications in navigation systems.

  • #31
We're two pages in and no closer to a resolution, so we're closing it.

There are a number of good technical papers on the detailed operation of the GPS system; if someone wants to recommend a few we can post links into this thread.
 
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