One way speed of light in one reference frame measurement

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Discussion Overview

The discussion revolves around the measurement of the one-way speed of light using an experimental setup involving two clocks positioned 100 kilometers apart. Participants explore whether this setup can resolve the conundrum associated with measuring the one-way speed of light without relying on roundtrip measurements or synchronization conventions.

Discussion Character

  • Debate/contested
  • Experimental/applied
  • Conceptual clarification

Main Points Raised

  • One participant proposes an experimental setup where two clocks are synchronized using light pulses sent to them, questioning if this leads to a one-way speed of light conundrum.
  • Another participant references previous discussions on similar topics, suggesting that the issue has been explored before.
  • A participant argues that the synchronization of the clocks assumes isotropy of light speed, thus potentially biasing the conclusion about one-way speed measurements.
  • One participant suggests that atomic clocks could be used to determine isotropy if they record the same elapsed time, but acknowledges the challenge of agreeing on the timing between the two locations.
  • Another participant reiterates that any measurement of one-way speed requires a synchronization convention, which fundamentally influences the outcome.

Areas of Agreement / Disagreement

Participants express disagreement regarding the feasibility of measuring the one-way speed of light without a synchronization convention. Some assert that such a measurement is impossible, while others explore potential methods to address the issue.

Contextual Notes

The discussion highlights limitations related to the assumptions of isotropy and the dependence on synchronization conventions, which remain unresolved.

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Two clocks with photo detectors are 100 kilometers apart at A and B. On the center of AB axis two light pulses are sent to the clocks , synchronizing them. Then a light signal is sent from A to B. The two stationary observers record the time from event at A to event at B. Is there a one way speed of light conundrum in this experimental setup ?
 
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Unlike the above references my experimental setup does not include roundtrips of light signals . And furthermore as long as the speed of light is isotropic it would not be necessary to know it's speed synchronizing the two clocks.
 
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morrobay said:
two light pulses are sent to the clocks , synchronizing them. ... Is there a one way speed of light conundrum in this experimental setup ?
Obviously this procedure only synchronizes the clocks if the one way speed of light is isotropic. So you are assuming your conclusion.

There is no possible experiment and no clever setup that can possibly measure a one way speed of anything without some synchronization convention. That convention determines the result.
 
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Could atomic clocks at A and B photo detectors that are started from signal at center of AB axis determine if the speed is isotropic ? The clocks are started at t1 . Then if both clocks at any t2 have recorded the same elapsed time then it seems by construction isotropy can be determined. Ok I see the problem with this : how do both A and B agree on t2
 
There is no possible experiment and no clever setup that can possibly measure a one way speed of anything without some synchronization convention. That convention determines the result.
 
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