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Re: Mass and Energy

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Am Sonntag000004, 04.01.2026 um 20:51 schrieb Paul.B.Andersen:
> Den 01.01.2026 17:19, skrev Stefan Ram:
>> "Paul.B.Andersen" <relativity@paulba.no> wrote or quoted:
>> :that mass could be converted to energy as
>> :predicted by Einstein's E = mc².
> 
> I resent very much that you:
> 1. Break threads so it is impossible to see to what you are responding.
> 2. Paraphrase and not quote.
> 
> I can guess that you were responding to my statement:
>   "The atom bomb proved in a very convincing way
>    that mass could be converted to energy as
>    predicted by Einstein's E = mc²."
> 
> This statement isn't very precise, but not wrong.
> So let's look at a more precise statement about
> what is happening in an atomic fission bomb:
> 
> One possible fission process is:
> 
> 1n + U-235 → Ba-141 + Kr-92 + 3n
> 
> The atomic weight (mass) of these are:
> 
> Left side:
> 1n      1.008664  u
> U-235 235.0439299 u
> -------------------
>        236.0525939 u = 3.919748214E-25 kg
> 
> Right side:
> Ba-141   140.914412 u
> Kr-92     91.926156 u
> 3n         3.025992 u
> ---------------------
>           235.866560 u = 3.916659047E-25 kg
> 
> Lost mass: m = 0.1860339 u = 3.089167695E-28 kg
> 
> E = mc² ≈ 2.776404839E-11 J
> 
>>
>>    I can spot three mistakes here right off the bat.
>>
>>         First, the phrase "mass could be converted to energy" is based on
>>    a misconception, since mass already /is/ a form of energy - there's no
>>    "conversion" happening. It's like saying, "water can be turned into a
>>    liquid" - no, water /is/ a liquid.
> 
> Note that m = 3.089167695E-28 kg is the _lost_ mass,
> it doesn't exist any more.
> So where has it gone?
> It is converted to E = mc² ≈ 2.776404839E-11 J of _kinetic energy_.
> Kinetic energy is not mass. Thus "convert".
> 
>>
>>         Second, "E=mc^2" only applies to systems at rest. In general,
>>    it's "E^2=(mc^2)^2+(pc)^2", where "p" is the system's momentum.
>>    (That basically says mass is the magnitude of the four-momentum.)
> 
> E = mc² is the energy content, or the energy equivalent of
> the mass m. Mass is invariant, so this equation is valid for
> all speeds of the mass.

You contradicted yourself!!

Here your claim is, that mass is invariant, while a little below you 
claim, that energy is conserved, while mass has vanished from a 
radioactive sample.

But you can't keep both claims, because they contradict each other.

So let's keep energy and regard matter as some strange form of energy.

I actually had this idea long ago and wrote kind of book about it:

https://docs.google.com/presentation/d/1Ur3_giuk2l439fxUa8QHX4wTDxBEaM6lOlgVUa0cFU4/edit?usp=sharing

(As proof of concept I had 'Growing Earth' in mind.)


TH

...

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Thread

Mass and Energy ram@zedat.fu-berlin.de (Stefan Ram) - 2026-01-01 16:19 +0000
  Re: Mass and Energy nospam@de-ster.demon.nl (J. J. Lodder) - 2026-01-01 22:38 +0100
  Re: Mass and Energy x <x@x.net> - 2026-01-02 10:03 -0800
  Re: Mass and Energy x <x@x.net> - 2026-01-02 10:06 -0800
    Re: Mass and Energy Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2026-01-02 21:07 +0100
  Re: Mass and Energy "Paul.B.Andersen" <relativity@paulba.no> - 2026-01-04 20:51 +0100
    Re: Mass and Energy Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2026-01-06 03:04 +0100
    Re: Mass and Energy Thomas Heger <ttt_heg@web.de> - 2026-01-06 09:15 +0100
      Re: Mass and Energy "Paul.B.Andersen" <relativity@paulba.no> - 2026-01-06 22:57 +0100
        Re: Mass and Energy Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2026-01-06 23:51 +0100
        Re: Mass and Energy "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-01-07 13:20 -0800
          Re: Mass and Energy "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-01-07 13:29 -0800
          Re: Mass and Energy Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2026-01-07 22:53 +0100

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