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On 11/13/2024 04:35 PM, Ross Finlayson wrote:It's usually considered that the lower energy photonsOn 11/13/2024 02:26 PM, J. J. Lodder wrote:>rhertz <hertz778@gmail.com> wrote:>
>That there was a relationship between energy and mass was suspected>
since the last years of XIX century.
>
By 1899, Poincaré derived such a relationship by using a thought
experiment with a "light cannon" and its recoil, once it shot a
pulse of
light. By equating the energy of the light pulse and the recoil of such
a cannon, it lead him to attribute to electromagnetic radiation a mass
equal to E/c? where E is the total energy of the radiation.
>
https://www.bjp-bg.com/papers/bjp2019_2_081-093.pdf
There you go again, clueless as usual.
Maxwell himself already predicted radiation pressure,
and he knew that EM fields must have energy.
Again, 'everyone' knew that in the late 19th century.
It was used extensively to extend thermodynamics
to include EM fields.
Maxwell was hardly original in this.
Kepler already postullated radiation pressure,
from the observation of comet tails being blown away from the sun,
but he could not quantify it.
Lebedev confirmed Maxwell's prediction quantitatively in 1900.
Poincare's thought experiment is merely a demonstration,
>
Jan
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Yeah, according to SR, the latest in the line of "solar sail"
experiments should be doing perfectly fine.
>
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Hey, maybe now you just solved why Casimir force needn't
have photons be electromagnetic, wow, you've just up-ended
an entire reason why mass-less charge-less photons are
any old thing needed to fit!
>
Or that it's photometric Casimir force, ....
>
These days some numb-skulls even say photons have mass
on the order of 10^10 less than an atom. Which is small, ....
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Yet, they never arrive at it having charge, ....
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Oh well, at least Einstein has "yes, ..., there is an ether
hypothesis and thus space in a sense plain exists", ...,
so light has somewhere to fly.
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... and a clock hypothesis.
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These days you ask physicists "what's photons" and half
of them are like "what do you want it to be, ...", which
is a usual sort of joke about those willing to leave out
their scruples for scrip.
>
>
You know, in linacs, the tracks end up looking pretty long,
while in ring cyclotrons, they warm up for a while, ...,
as with regards to what "numbers" they give the SR-ians.
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