Re: E = 3/4 mc? or E = mc?? The forgotten Hassenohrl 1905 work.

On Sat, 7 Dec 2024 21:35:57 +0000, J. J. Lodder wrote:

On 2024-12-07 16:03:31 +0000, ProkaryoticCaspaseHomolog said:
[missing article on my server, sorry about mixed up quote levels]
>

On Sat, 7 Dec 2024 11:03:24 +0000, J. J. Lodder wrote:
>
Sure, you can be inconsistent, if you choose to be.
Don't expect meaningful results.
>
It would not make sense to quantify hypothetical variations in the
speed of light in terms of the post-1983 meter. But they would make
sense in terms pre-1983 meters. Or (assuming some incredible ramp-up
in technology, perhaps introduced by Larry Niven-ish Outsiders) in
terms of a meter defined as the distance massless gluons travel in
1/299,792,458 of a second. Or gravitons... :-)
>
Completely irrelevant,
and it does not get you out of your conceptual error as stated above.
>
Summmary: There must be:
1) a length standard, 2) a frequency standard [1], and 3) c
>
Two of the three must be defined, the third must be measured.
Pre-1983  1) and 2) were defined, and 3), c was measured.
Post-1983 2) and c are defined, 1) must be measured.
So in 1983 we have collectively decided that any future refinement
in measurement techniques will result in more accurate meter standards,
not in a 'better' value for c.  [2]
>
You don't "get" the point that I was trying to make. Let us review

>
I do get it, and it is wrong.
>

| Resolution 1 of the 17th CGPM (1983)

[snip boilerplate material]
>

Gamma ray burst observations have constrained the arrival times
between the visible light and gamma ray components of the burst to
be equal to within 10^-15 of the total travel time of the burst.

[snip more irrelevancies]
>
This is irrelevant for the issue of E=mc^2.
Differential travel times are a test for a non-zero photon mass, if any.
>

Definitions are BASED ON state-of-the-art known physics. They do not
DETERMINE physical law.

>
Are you really incapabable of understanding
that all this is about metrology, not physical law?
No definition of units can ever determine or change any physical law.
>

Finally, an excercise for you personally.
You quoted a pre-2018 experiment that verified that E=mc^2
to some high accuracy. (using the measured value of Planck's constant)
Post-2018, Planck's constant has a defined value,
and  E=mc^2 is true by definition. (of the Joule and the kilogram)
>
So E=mc^2 can no longer be verified by any possible experiment.
Now:
Ex1) Does this make the experiment you quoted worthless?
>
Not at all.

>
Correct.
>

Ex2) If not, what does that experiment demonstrate?
>
It would demonstrate an inadequacy in the definitions that must be
addressed in some future conference when the discrepancies have been
better characterized.

>
I'm sorry, but this is not the right answer,

So what are you saying, then? Are you saying that, because of the
definition of E=mc^2, it is totally required that 1 gram of electrons
annihilating 1 gram of positrons completely to electromagnetic
radiation must NECESSICARILY yield the same amount of energy as 1 gram
of protons annihilating 1 gram of antiprotons completely to electro-
magnetic radiation? That the equality of these two values is a matter
of definition, not something to be established by experiment?
Are you saying that because the current definition of c is
299,792,458 meters per second regardless of wavelength, that questions
as to whether gamma rays travel faster than visible light rays are
totally nonsensical?