Re: New version of my annotations to SRT

Am Freitag000019, 19.04.2024 um 09:38 schrieb Mikko:

On 2024-04-19 05:50:28 +0000, Thomas Heger said:
 

Am Sonntag000018, 18.02.2024 um 12:00 schrieb Mikko:

On 2024-02-18 05:48:12 +0000, Thomas Heger said:
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Am 17.02.2024 um 17:16 schrieb Python:

Le 17/02/2024 à 15:40, Mikko a écrit :

On 2024-02-17 13:33:38 +0000, Python said:
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Le 17/02/2024 à 11:47, Mikko a écrit :

On 2024-02-17 09:36:42 +0000, Thomas Heger said:
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Am 16.02.2024 um 09:46 schrieb Athel Cornish-Bowden:

On 2024-02-16 06:20:15 +0000, Thomas Heger said:
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[ … ]

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Can you quote the sentence in question?

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sure:
page 22, roughly in the middle
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"We will now determine the kinetic energy of the electron. If an
electron moves from rest at the origin of co-ordinates of the
system K
along the axis of X under the action of an electrostatic force X,
..."

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Is this your translation? Is "the axis of X" what is normally
called the
x-axis in English? Maybe you could quote it in German so that someone
who knows more German than I do can comment. Anyway, I agree that
calling the abscissa axis the x-axis is not ideal, but it's very
commonly done. In that case X is not a variable.

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I'm actually critizising a certain text, not the work of Einstein
per se.
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So, my topic is this particular English translation.

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When a real professor evaluates a translation the main criterion is
whether the translation preseves the meaning of the text.
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Anyway this kinda sloppy translation is not quite a big deal, there
is absolutely no ambiguity. Moreover Heger was pretending that "A"
was used with two different meanings in a single sentence, not "X",
so he is blatantly lying (again).

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The symbol A is indeed used in several different meanings but the
meaning is always specified. But Heger also claimed (falsely) that
Einstein used X in two different meanings in the same sentence:
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On 2024-02-16 07:20, Thomas Heger said:

Am 15.02.2024 um 11:32 schrieb Paul B. Andersen:

Den 15.02.2024 07:10, skrev Thomas Heger:

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But Einstein gave this another kick and used the same symbol twice
with
different meanings within a single sentence.

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Can you quote the sentence in question?

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sure:
page 22, roughly in the middle
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"We will now determine the kinetic energy of the electron. If an
electron moves from rest at the origin of co-ordinates of the system
K along the axis of X under the action of an electrostatic force X, ..."

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In Einstein's text "X-Achse" is clearly different from plain "X".

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Definitely.
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the 'x-Achse' had a name,

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True.
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 which was 'X'.

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No, its name was "X-Achse", and still is.
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No, that's wrong.
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If 'x-Achse' ('x-axis' in German) was named 'X', then 'X-Achse' would be in long form:

 "X-Achse" is a single word. It means wohat it means, independently of
what it parts might otherwise mean, just like the meaning of the word
"fair" is independent of the meaning of the word "air".
 

No, because symbols in physical expressions and equations are 'case-sensitive' (as the problem is called today).
Therefore, the symbol 'x' is not equal to 'X'.
The symbol 'X' was defined as name of the x-axis of system K.
That's why it is allowed to expand 'X' to 'x-axis of system K'.
And once defined, it is not allowed to use the same symbol for other purposes.
But reuse of symbols was common in Einstein's paper.
But that's a very bad habit, because it made interpretations of some equations very difficult.
Another instance of the same problem was the use of 'P'.
'P was used for pressure (usually 'p' is used for that) and for potential one chapter later.
Also the letter 'A' was used for very different purposes (eight in total).
But such habits are at least nasty.
TH