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

Am Dienstag000020, 20.08.2024 um 08:16 schrieb Python:

Le 20/08/2024 à 08:02, Thomas Heger a écrit :

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!

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

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AB was actually meant as:
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distance from A to B,
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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).

 Yes it would be absurd. BTW you are conflating affine spaces with
vector spaces here.
 

Besides of this little formal issue (actually meant was |r_AB| ),

 Well, Thomas, this is utterly ridiculous. Any reader understands what
AB as it appears in 2AB/(t'_A - t_A) is the distance AB. From high
school to Ph. D.

"the distance AB" is not equal to "AB"!
Actually meant was: 'A' and 'B' denote locations in a certain coordinate system, hence are technically position vectors.
Because a product of vectors is possible, 'AB' would be the product of A and B.
If you want to adress the distance from point 'A' to point 'B' you cannot simply say 'AB'.
Whether or not 'any reader understands' is patently irrelevant.

 

Einstein had not written AB/c (or r_AB/c).

 It appears after ONE step of elementary algebra from the two first
equations on page 3 there :
 https://users.physics.ox.ac.uk/~rtaylor/teaching/specrel.pdf
 Do you really think that readers (physicists) in 1905 couldn't
immediately recognize this from two so simple equations, Thomas ?

SRT is certainly a socio-cultural mystery and the question you wrote is also a mystery.
I have not dealt with that question, but here with a formal issue.
My point was, that 'AB' is not a valid symbol for 'distance from point A to point B'.

What he had actually written was
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r_AB/(c-v)

 This is in paragraph 3. We are dealing with paragraph 2 here.

Sure, but §3 does not contain the equation you quoted.
to remind you, that's what you have written:
 >"... It is. It is explained in my initial post : What is (AB)/c to you?.."

Einstein's method did not allow mutally symmetric synchronization.

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The procedure can be proven symmetric. Face it.

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No, it wouldn't.

 It can be shown. This is a very simple exercise even for high school
students. You cannot seriously pretend to be an engineer Thomas.
 

I take as example two spaceships in 1 lightseconds distance, which are called A and B.
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Both have a HUGE clock strapped to that spaceship and use a VERY HUGE telescope to read the clock of the other ship.

 The is NO reading of another clock with a telescope in the procedure
described at paragraph 2 (nor elsewhere in the article)

Sure, there ain't.
But it should, because relativity requires mutually symmetric relations.
This means:
if one side can apply a certain method, than the other side should be allowed to apply the same method, too.
If you would not require this, you would drop the essence of relativity, which says, that all inertial frames of reference are of equal rights.
...
TH