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Re: Annotated version of SRT

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Am 25.04.2022 um 21:22 schrieb JanPB:
> On Monday, April 25, 2022 at 12:52:14 AM UTC-7, Thomas Heger wrote:
>> Am 24.04.2022 um 10:52 schrieb JanPB:
>>
>>>> But even if so, x' would still be zero.
>>>
>>> Yes, you get x' = 0 for the emitter/receiver because its location
>>> by construction of this experimental setup satisfies x = vt at
>>> all times t, hence the corresponding x' value is:
>>>
>>> x' = x - vt = 0
>>>
>>> throughout.
>> Here you actually agree, that x'=0 must be true.
>
> For the *light source*.


No, this is wrong because Einstein had a different setting:

[quote]

"From the origin of system k let a ray be emitted at the time τ'along 
the X-axis to x' and at the time τ_1 be reflected thence to the origin of 
the coordinates, ..."

[/quote]

The system k was the moving system, hence Einstein wanted a moving 
emitter and a stationary mirror.

The mirror should be located at x', because the text says so.

Because the zero spot of k has the x-coordinate in K of
xsi_0 = x_0 * v*t
we end up at the zero spot of K, if we subtract v*t from xsi_0.


> The differentiation OTOH is taken with respect to the *mirror* position
> (denoted by  x'  by the abuse of notation) which is nonzero (obviously).

No, x' is OBVIOUSLY the zero spot of K.

It makes no sense to write partial differential equations for a problem, 
where only the x-axis is involved. But still we cannot differentiate a 
fixed position, at least not in K.

Seen from the emitter, the mirrors moves and we have the usual relation 
v= x'/d tau.

Now Einstein used the inverse 1/v in his equation, what is blatant nonsense.

This is nonsense, because the possible case of v=0 would produce an 
infinite term.

I have complained about this fact a number of times, but instead of a 
positive reply I was called a nutcase.

>>> You get confused by the multiple uses of x' (the standard notational
>>> abuse). What Einstein does is he puts the emitter/receiver at x' = 0
>>> and the mirror at some nonzero value of x' which he also calls x'
>> 'notational abuse' is in my world 'plain wrong'.
>
> No, it's the standard. The term "notational abuse" is a bit of
> a joke, it does not indicate anything is wrong. This notation is so
> frequently used because the alternative can make make formulas
> harder to read.

OK, I cannot decode insider jokes, because I'm actually an outsider.

So: to me a "notational abuse" is an error, period.

>> IOW: if a veriable is defined somehow, that definition remains valid,
>> unless the veriable is redefined with a new meaning explicitly.
>
> In some cases it's not mentioned explicitly by a hundreds-years old
> convention. Everyone in the profession knows about it.

Is this also an insider joke?

>> So: we are not allowed to declare something is just 'notational abuse'.
>
> Yes, we are and we do. This is a required part of everyone's education
> in science, like the scientific notation, say, or the use of the Greek alphabet.


I have actually occasionally the impression, that education of 
physicists includes brainwashing.

>> Instead we have to use even the wrong definitions from the text, if
>> there are any, because we must not change a text to our own liking.
>
> The definition is not wrong. Only a small change of context occurs
> silently. Everyone understands that sort of thing.

???????????

>> A text is what it is, whether we like it or not.
>
> I do like it, and the text is correct.
>
>>> (notational abuse). Then he varies the location of the mirror and
>>> compares the resulting differences, this is what the differentiation
>>> with respect to x' that follows does.
>> No,
>
> Yes.
>
>> Einstein wrote, that the ray was emitted from the zero spot of k.
>> This is the moving system.
>
> OK.
>
>> The zero spot of k has a coordinate in K, too, which is
>> xsi_0= x_0 + v*t
>
> ksi  is not  K's  coordinate.

Sure, the zero spot of k has also a coordinate in K.

The relation is totally simple: xsi_0= x_0 * v*t

>
>> Since the emitter was located at a fixed point in k with cordinates in k
>> xsi=0, eta=0,m zeta=0, the mirror cannot be place at the same spot.
>
> The mirror is not at the same spot.

Of course the mirror cannot coincide with the  emitter.

>> Contrary to your assumption, we are forced to assume, that x' was the
>> position of the MIRROR, even if Einstein had not written so.
>
> No, that's wrong.
>
>> There is actually no other possibility.
>
> No, incorrect.
>

TH

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Re: Annotated version of SRT JanPB <filmart@gmail.com> - 2022-04-21 13:48 -0700
  Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-22 09:00 +0200
    Re: Annotated version of SRT JanPB <filmart@gmail.com> - 2022-04-22 01:41 -0700
      Re: Annotated version of SRT Dong Vassilikos <saox@cowrpsho.rb> - 2022-04-24 12:23 +0000
    Re: Annotated version of SRT Python <python@example.invalid> - 2022-04-22 15:39 +0200
      Re: Annotated version of SRT Maciej Wozniak <maluwozniak@gmail.com> - 2022-04-22 07:11 -0700
      Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-23 07:55 +0200
        Re: Annotated version of SRT Michael Moroney <moroney@world.std.spaamtrap.com> - 2022-04-23 03:34 -0400
          Re: Annotated version of SRT Python <python@example.invalid> - 2022-04-23 11:52 +0200
            Re: Annotated version of SRT Maciej Wozniak <maluwozniak@gmail.com> - 2022-04-23 05:49 -0700
            Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-24 08:07 +0200
              Re: Annotated version of SRT JanPB <filmart@gmail.com> - 2022-04-24 01:52 -0700
                Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-25 09:52 +0200
                Re: Annotated version of SRT JanPB <filmart@gmail.com> - 2022-04-25 12:22 -0700
                Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-26 07:02 +0200
                Re: Annotated version of SRT JanPB <filmart@gmail.com> - 2022-04-25 23:52 -0700
                Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-26 22:24 +0200
                Re: Annotated version of SRT JanPB <filmart@gmail.com> - 2022-04-26 17:35 -0700
                Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-27 07:59 +0200
                Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-28 07:14 +0200
                Re: Annotated version of SRT JanPB <filmart@gmail.com> - 2022-04-28 01:45 -0700
                Re: Annotated version of SRT Rady Konoe <akde@oakoradn.en> - 2022-04-28 09:03 +0000
                Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-29 08:08 +0200
                Re: Annotated version of SRT JanPB <filmart@gmail.com> - 2022-04-29 20:51 -0700
                Re: Annotated version of SRT Maciej Wozniak <maluwozniak@gmail.com> - 2022-04-29 21:03 -0700
                Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-30 07:47 +0200
                Imbecile Thomas Heger perseveres "Dono." <eggy20011951@gmail.com> - 2022-04-30 07:00 -0700
                Re: Imbecile Thomas Heger perseveres Richard Hachel <r.hachel@tiscali.fr> - 2022-04-30 14:44 +0000
                Re: Imbecile Thomas Heger perseveres "Dono." <eggy20011951@gmail.com> - 2022-04-30 08:19 -0700
                Re: Imbecile Thomas Heger perseveres Richard Hachel <r.hachel@tiscali.fr> - 2022-04-30 15:28 +0000
                Re: Imbecile Thomas Heger perseveres Odd Bodkin <bodkinodd@gmail.com> - 2022-04-30 15:33 +0000
                Re: Imbecile Thomas Heger perseveres Richard Hachel <r.hachel@tiscali.fr> - 2022-04-30 17:56 +0000
                Re: Imbecile Thomas Heger perseveres Thomas Heger <ttt_heg@web.de> - 2022-04-30 20:15 +0200
                Re: Annotated version of SRT Odd Bodkin <bodkinodd@gmail.com> - 2022-04-28 16:44 +0000
                Re: Annotated version of SRT Maciej Wozniak <maluwozniak@gmail.com> - 2022-04-28 23:15 -0700
                Re: Annotated version of SRT Python <python@example.invalid> - 2022-04-29 14:30 +0200
                Re: Annotated version of SRT Maciej Wozniak <maluwozniak@gmail.com> - 2022-04-29 06:45 -0700
                Re: Annotated version of SRT Richard Hachel <r.hachel@tiscali.fr> - 2022-04-30 19:50 +0000
                Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-29 08:22 +0200
                Re: Annotated version of SRT Odd Bodkin <bodkinodd@gmail.com> - 2022-04-29 12:52 +0000
                Re: Annotated version of SRT Odd Bodkin <bodkinodd@gmail.com> - 2022-04-29 13:06 +0000
                Re: Annotated version of SRT Maciej Wozniak <maluwozniak@gmail.com> - 2022-04-29 06:47 -0700
          Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-24 07:49 +0200
            Re: Annotated version of SRT JanPB <filmart@gmail.com> - 2022-04-24 01:23 -0700
              Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-24 11:08 +0200
                Re: Annotated version of SRT JanPB <filmart@gmail.com> - 2022-04-24 05:14 -0700
                Re: Annotated version of SRT JanPB <filmart@gmail.com> - 2022-04-24 12:46 -0700
                Re: Annotated version of SRT Dong Vassilikos <saox@cowrpsho.rb> - 2022-04-24 21:09 +0000
                Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-25 10:23 +0200
                Re: Annotated version of SRT Michael Moroney <moroney@world.std.spaamtrap.com> - 2022-04-24 12:56 -0400
                Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-25 10:09 +0200
                Re: Annotated version of SRT Michael Moroney <moroney@world.std.spaamtrap.com> - 2022-04-25 11:51 -0400
                Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-26 07:22 +0200
        Re: Annotated version of SRT Cody Sakellariou <yall@ckcldcdd.ar> - 2022-04-23 07:59 +0000
        Re: Annotated version of SRT Odd Bodkin <bodkinodd@gmail.com> - 2022-04-23 12:56 +0000
  Re: Annotated version of SRT Dong Vassilikos <saox@cowrpsho.rb> - 2022-04-24 21:21 +0000

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