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

On 2024-08-18 09:57:35 +0000, Thomas Heger said:

Am Samstag000017, 17.08.2024 um 14:52 schrieb Python:

**An Interesting Case of Mental Blockage and Cognitive Dissonance:**
 *Einstein-Poincaré Synchronization Procedure and Dr. Lengrand*
 What’s fascinating about certain cranks is that just when you think you’ve seen all the absurdities they can come up with, they manage to produce something even worse. Their cognitive dissonance and ability to pull out bizarre notions from who knows where, on top of a perfectly well-defined technical procedure, is astonishing. We’ve seen this before with GPS, where Hachel invents all sorts of fantasies, like atomic clocks in the receivers or synchronization with a clock infinitely far away in a fourth spatial dimension...
 This is a report of exchanges on the synchronization procedure described by Einstein in his 1905 paper, discussions that took place 17 years ago and more recently on sci.physics.relativity and fr.sci.physique.
 https://groups.google.com/g/fr.sci.physique/c/KgqI9gqTkR8/m/oMc9X0XjCWMJ
 *Reminders on the Procedure:*
 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.
 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.
 *Steps of Einstein's Method:*
 When clock A shows t_A, a light signal is emitted from A towards B.
 When this signal is received at B, clock B shows t_B, and a light signal is sent from B back towards A.
 When the signal is received at A, clock A shows t'_A.

 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.

The method needs not be symmetric. It is sufficient that the result is.
Perhaps a symmetric method would be better in some cases. A possible
symmetric method is to use a signal source that is equally far from
both clocks.
The result of Einstein's method is symmetric in the sense that if A is
synchronized with B then B is synchornized with A.
--
Mikko