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Re: Annotated version of SRT

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Am 24.04.2022 um 18:56 schrieb Michael Moroney:
> On 4/24/2022 5:08 AM, Thomas Heger wrote:
>> Am 24.04.2022 um 10:23 schrieb JanPB:
>>
>>>>>> Before you crank out insults, you should at least ask google for the
>>>>>> meaning of 'Gallileo transformation'.
>>>>>>
>>>>>> The very first result would be this:
>>>>>>
>>>>>> https://en.wikipedia.org/wiki/Galilean_transformation
>>>>>>
>>>>>> Quote:
>>>>>>
>>>>>> " x' = x- v*t "
>>>>>>
>>>>> Just because the Galilean transformation is x' = x-vt doesn't mean
>>>>> every
>>>>> instance of "x'=x-vt" is the Galilean Transform.
>>>>> This is an example of the logical fallacy: If A then B implies If B
>>>>> then
>>>>> A. (If NOT B then NOT A is true, however)
>>>> You are absolute right, that this was not meant as Galilean
>>>> transformation, even if the equation of that transform was used.
>>>>
>>>> In fact Einstein made an error:
>>>>
>>>> he used 'x' in his equation "x' = x- v*t"
>>>
>>> No, this is correct.
>>>
>>>> Instead of that, actually:
>>>> x' = xsi - v*t
>>>> was meant with xsi=0.
>>>
>>> No.
>>>
>>>> The setting was: a light beam was sent from the zero spot of k to the
>>>> point x'. There was a mirror placed, which reflected the beam back to
>>>> the source.
>>>>
>>>> Now the zero spot of k has the xsi-coordinate xsi=0.
>>>>
>>>> This point moves along the X-axis of K with velocity v. Now we have:
>>>> x' = xsi - v*t (correcting Einstein's obvious error from above).
>>>
>>> No, this is wrong.  x'  is defined as  x - vt.  It's just a
>>> definition of a new
>>> variable called  x',  introduced for convenience.  One could call this
>>> "Galilean transformation" only in the sense that the coordinates  (x,
>>> y, z, t)
>>> are being changed to  (x', y, z, t) the "Galilean" way but the physical
>>> context is wrong: the term "such-and-such transform" usually refers
>>> to two observers whose space and time coordinates are being related
>>> by the transformation. But here the context is that we have only one
>>> observer (K) who for convenience relabels one of the axes.
>>
>> What did you mean by:
>>
>> "It's just a definition of a new variable called  x',  introduced for
>> convenience."
>>
>> To me this sounds like nonsense, because what kind of convenience is
>> required and for which purpose? Where was that purpose introduced?
>
> It's so a certain calculation or transformation performed repeatedly can
> be done just once and assigned to a symbol, and the symbol used instead
> of repeating the calculation/transformation again and again.
>
> You are already familiar with this concept, it the same as writing "γ"
> instead of "1/√(1-v²/c²) repeatedly in SR calculations. Similarly,
> Einstein wrote "x'" = "x-vt" to make it clearer for his target audience
> because it simplifies his math.  (since you are not among his target
> audience, it's understandable that you get confused)
>>
>>>> For instance del x' in the denominator would not make much sense, if
>>>> x'=0.
>>>
>>> I'm compelled to ask at this point: do you know calculus?
>>>
>>
>> To me it is totally idiotic to put zero into a denominator in a
>> differential equation.
>
> By writing that, it looks like you don't know calculus since "/dx'" or
> "del x'" is just PART of a differentiation symbol.


Ok, I made actually an error, because del tau referrs to the velocity v, 
but seen from system k, not from K.

If the position of x' is at the zero spot of K, it would not move in K, 
because it is always at the same (zero-)spot.

The position of the mirror moves only in k, in respect to the emitter at 
the zero spot of k with velocity v*tau to the left (the direction of 
smaller xsi-values).

Now the derivative in K dx'/dt=0, because x' remains zero.

Seen from k, the derivative dx'/d tau would be v and the inverse
d tau/dx'= 1/v

For partial differential equations I would see no need, because there is 
actually only the very simple relation dx'/d tau =v.


TH

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Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-21 08:53 +0200
  Re: Annotated version of SRT Reinhardt Behm <rbehm@hushmail.com> - 2022-04-21 13:13 +0000
    Re: Annotated version of SRT Paul Alsing <pnalsing@gmail.com> - 2022-04-21 07:32 -0700
    Re: Annotated version of SRT JanPB <filmart@gmail.com> - 2022-04-21 13:51 -0700
    Re: Annotated version of SRT nospam@de-ster.demon.nl (J. J. Lodder) - 2022-04-21 23:24 +0200
      Re: Annotated version of SRT Maciej Wozniak <maluwozniak@gmail.com> - 2022-04-21 21:10 -0700
      Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-22 08:38 +0200
        Re: Annotated version of SRT nospam@de-ster.demon.nl (J. J. Lodder) - 2022-04-22 11:00 +0200
          Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-23 08:07 +0200
        Re: Annotated version of SRT RichD <r_delaney2001@yahoo.com> - 2022-04-23 14:59 -0700
          Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-24 07:36 +0200
          Re: Annotated version of SRT nospam@de-ster.demon.nl (J. J. Lodder) - 2022-04-24 10:41 +0200
            Re: Annotated version of SRT Maciej Wozniak <maluwozniak@gmail.com> - 2022-04-24 01:59 -0700
            Re: Annotated version of SRT Thomas Heger <ttt_heg@web.de> - 2022-04-26 09:02 +0200
  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 Odd Bodkin <bodkinodd@gmail.com> - 2022-04-28 16:44 +0000
            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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