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Re: Mass and Energy

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On 1/6/2026 1:57 PM, Paul.B.Andersen wrote:
> Den 06.01.2026 09:15, skrev Thomas Heger:
>> Am Sonntag000004, 04.01.2026 um 20:51 schrieb Paul.B.Andersen:
>>>
>>> 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.
> 
> 
> Invariant means "the same in all frames of reference"
> or "independent of speed".
> 
> It does _not_ mean "constant".
> 
> Mass is invariant.
> The mass of an object is the same in all frames of reference.
> The mass of an object does not depend on the speed of the object.
> 
> But mass can change. Heat the object, and its mass will increase,
> 
> I have told you before, but I know you will not learn.
> You never do.
> 
> 

Its odd to think of a cup of water as the water evaporates. The cup is 
an object with its own mass. But, now its holding water. So, the cup 
"weighs" more in a sense... But, as the water evaporates, that weight 
will go back to the weight of the original cup...

Think of two equal mass cups on a scale. They balance. Add water to one, 
its not balanced. However, the water will evaporate and the scale shall 
go back to balanced over time?

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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 x <x@x.net> - 2026-01-02 15:40 -0800
      Re: Mass and Energy x <x@x.net> - 2026-01-02 16:05 -0800
        Re: Mass and Energy Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2026-01-03 14:30 +0100
      Re: Mass and Energy Thomas Heger <ttt_heg@web.de> - 2026-01-04 09:06 +0100
        Re: Mass and Energy nospam@de-ster.demon.nl (J. J. Lodder) - 2026-01-04 12:28 +0100
          Re: Mass and Energy Thomas Heger <ttt_heg@web.de> - 2026-01-06 09:03 +0100
            Re: Mass and Energy nospam@de-ster.demon.nl (J. J. Lodder) - 2026-01-06 10:56 +0100
              Re: Mass and Energy Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-01-06 06:52 -0800
                Re: Mass and Energy nospam@de-ster.demon.nl (J. J. Lodder) - 2026-01-06 16:12 +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 "Paul.B.Andersen" <relativity@paulba.no> - 2026-01-06 22:12 +0100
        Re: Mass and Energy "Paul.B.Andersen" <relativity@paulba.no> - 2026-01-06 22:27 +0100
        Re: Mass and Energy Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-01-06 13:43 -0800
          Re: Mass and Energy Python <python@cccp.invalid> - 2026-01-06 21:46 +0000
            Re: Mass and Energy Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-01-07 04:32 -0800
        Re: Mass and Energy Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2026-01-06 23:27 +0100
          Re: Mass and Energy Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-01-07 04:14 -0800
          Re: Mass and Energy "Paul B. Andersen" <relativity@paulba.no> - 2026-01-07 22:18 +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 Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2026-01-07 05:12 +0100
            Re: Mass and Energy Maciej Woźniak <mlwozniak@wp.pl> - 2026-01-07 08:16 +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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