Re: [SR and synchronization] Cognitive Dissonances and Mental Blockage

Am Montag000019, 19.08.2024 um 14:56 schrieb Python:

Le 19/08/2024 à 08:44, Thomas Heger a écrit :

Am Sonntag000018, 18.08.2024 um 12:05 schrieb Python:
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Two identical clocks, A and B, are stationary relative to each other at a certain distance. Their identical functioning (within measurement accuracy) allows us to assume that they "tick at the same rate." NOTHING more is assumed, especially regarding the time they display; the purpose is PRECISELY to adjust one of these clocks by applying a correction after a calculation involving the values indicated on these clocks during specific events, events that occur AT THE LOCATION OF EACH CLOCK.
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Einstein’s procedure is not strictly a synchronization procedure but a method to VERIFY their synchronization. This is the main difference from Poincaré’s approach. However, it can be proven that Poincaré’s method leads to clocks synchronized in Einstein’s sense. You can also transform Einstein’s verification method into a synchronization procedure because it allows calculating the correction to apply to clock A.
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*Steps of Einstein's Method:*
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When clock A shows t_A, a light signal is emitted from A towards B.
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When this signal is received at B, clock B shows t_B, and a light signal is sent from B back towards A.
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When the signal is received at A, clock A shows t'_A.

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Relativity requires mutally symmetric methods. So if you synchronize clock B with clock A, this must come to the same result, as if you would synchronize clock A with clock B.

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It is.

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No, it is not!

 It is. It is explained in my initial post : What is (AB)/c to you?

AB was actually meant as:
distance from A to B,
even if A and B are in fact position vectors, hence AB would usually be the scalar product of A and B (what is absurd).
Besides of this little formal issue (actually meant was |r_AB| ), Einstein had not written AB/c (or r_AB/c).
What he had actually written was
r_AB/(c-v)

 

Einstein's method did not allow mutally symmetric synchronization.

 The procedure can be proven symmetric. Face it.

No, it wouldn't.
I take as example two spaceships in 1 lightseconds distance, which are called A and B.
Both have a HUGE clock strapped to that spaceship and use a VERY HUGE telescope to read the clock of the other ship.
Now clock A shows 12 o'clock and zero seconds.
Ship B reads this at time 12 o'clock plus 1 second, but turns the own clock (showing 12 o'clock plus one seconds) back by one second.
Now the observer of ship A reads the clock from ship B and reads 12 o'clock plus zero seconds, while the own clock shows 12 o'clock plus one seconds.
This is regarded as an error and the own clocks as being ahead, hence it was turned back to 12 o'clock plus zero seconds.
This is seen from ship B, where the own clock shows actually 12 o'clock plus one second. This is corrected by adjustment of one second, by which that clock is turned backwards.
This could go on forever, while both clocks would stand still.
But certainly this is not what you would call 'synchronization'.
TH
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