At 02:53 pm 23/01/2006 -0500, Stephen wrote:
>
> Actually it was my gedanken, or rather my quote of Einstein's gedanken
> experiment. But you're right, force is necessary to change the
> momentum of the rock/photon.
>
> But we can deal with the momentum issue. The rock can exchange
> momentum with the person who catches it _without_ exchanging more than
> a negligible amount of energy, and it's the total energy we were
> concerned with. Just make the planet on which the person who catches
> it is sitting sufficiently massive, so that the planet's motion, and
> by extension the motion of the person, is negligible.
>
> We see this effect all the time in real life. Bounce a ball off a
> hard, solid wall. The ball's momentum reverses, which implies the
> wall gained momentum equal to twice what the ball had to start with,
> but if it's a good hard rubber ball and the wall is good and solid,
> the ball loses almost none of its energy.
> The wall gains momentum but (almost) no energy.
That raises an interesting point. If we reduce everything
to strain energy, in other words if we recognised that
stress is really only an alias for strain, and is measured
from a false datum. i.e. it is applied stress not total
stress {cf. PV^6 = a constant relation for water on Prof.
Chaplin site) then we would realise that the positive
energy (expansion) was in fact equal to the negative
energy (compression).
The only reason we need the concept of energy (and force)
at all, is that we measure things from false origins.
We have to find the true origins, the real boundaries
(maxima, minima, points of inflection, etc.).
Now I don't expect anyone who is psychologically committed
to the scientific status quo to take these assertions
seriously, raising as they do, enormous cognitive dissonance.
However, I know I'm right, I know I can prove it to any
open minded philosopher, and I am therefore boldly stating
it here as a kind of claim stake at Sutter's Mill. 8-)
Cheers,
Frank Grimer
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Sir Brian had a battleaxe with great big knobs on.
He went among the villagers and blipped them on the head.
On Wednesday and on Saturday,
Especially on the latter day,
He called on all the cottages and this is what he said:
"I am Sir Brian!" (Ting-ling!)
"I am Sir Brian!" (Rat-tat!)
"I am Sir Brian,"
"As bold as a lion!"
"Take that, and that, and that!"
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