Re: refutation of the nonreality of energy

[Leigh Palmer <palmer@SFU.CA>]

I do know that things I am saying here challenge the beliefs of
many who read this group. Please realize that I shared these same
beliefs for some time myself, but Feynman and Burke relieved me
of those particular misconsceptions by making me think. In what
follows I am saddened by the vibes coming from a man who bears
what I consider an entirely appropriate surname. It means I'm not
getting through, of course. I've been a teacher for 33 years so I
understand the signal. Nonetheless I will persist, hoping still
that by doing so I can help others to understand.

This all may sound religious; perhaps it is. Please bear with me.
I have stopped reading the other strands in phys-l to concentrate
on this one.

At 04:34 -0700 8/5/99, John Denker wrote:
> At 11:20 PM 8/4/99 -0700, Leigh Palmer wrote:
> > Well, here it is. I hope someone is still reading me. Sometimes I
> > don't think I'm getting through.
>
> You're not.  Relatively little of your recent note was comprehensible to me.
>
> Here are the clearest parts, which I will answer.
>
> > > The typical person has more experience with stones than with pure energy,
> > > but that doesn't make one more real than the other.  Have you ever tried to
> > > land a plane, starting with too much energy?  A pilot's inventory of energy
> > > is as real and as important as a mason's inventory of stones.
> >
> > Please tell me, what is "pure energy"? That is an entity with which
> > I am unacquainted, and which I believe does not exist. Can you tell
> > me how to prepare pure energy? If that can be done I will be most
> > surprised!
>
> Here's how:  take two airplanes, alike in every relevant aspect, except
> that one of them has a lot more energy.  It could have more altitude and/or
> more airspeed;  the form doesn't matter.  But you will find that trying to
> land that airplane is very different from trying to land the other.  How do
> I explain this to my students?  I tell them about energy.  It works for them.
>
> If it doesn't work for you, well, that's your problem.  Please don't foist
> your problems onto vulnerable students who will have to go out into the
> real world where real people use local conservation of energy all the time.

When one applies the law of conservation of energy to a system one
must first isolate the system. The next requirement is that one must
observe the system from an appropriate frame. Any inertial frame will
do for this purpose. An airplane, flying high or low, is not an
isolated system. When one ascribes a potential energy to and
localizes within the airplane one is making use of a fiction adopted
for the purpose of getting around the requirements of isolation and
frame inertiality specifically for the purpose of employing something
that resembles the law of conservation of energy in a common case, a
mechanics problem on Earth's surface. What one probably really uses
in the case John describes is what I call the roller coaster formula.
It is not really the fundamental law of conservation of energy
because it includes a conscious fiction, the gravitational potential
energy *of the airplane*. The gravitational potential energy cannot
be localized. It resides in a much larger system which includes the
Earth. One should never lose sight of this fact when trying to
localize energy.

It takes little effort to warn students that you are doing something
that is not quite right when you derive the gravitational potential
energy term mgh, and it's not just that one must establish a zero. I
believe it is worth taking the trouble to do so even if it only sets
a flag in the minds of a small number among them to be more critical
in the future.

> > > Field energy is distributed in space, but not in "all" of space.  It must
> > > be in very particular parts of space.  Energy is not just globally
> > > conserved, it is *locally* conserved, which is a stronger statement.  That
> > > is to say, it can't disappear from place A and reappear at place B without
> > > crossing the boundary (any boundary we choose) between A and B.
> >
> > What is your evidence that it is "crossing"? (That is as bad as
> > "flowing" in my book.)
>
> By "crossing" I meant "flowing across" so we agree on at least this bit of
> terminology!
>
> > Can you detect its crossing without asking
> > and answering the question "What changes in energy have occurred
> > in the systems on either side of the boundary?"
>
> Sometimes I can detect it;  usually in order to make my point all I need to
> do is prevent it, perhaps by surrounding point A with a physical
> energy-boundary such as a Dewar flask ("Thermos bottle").  In those rare
> cases where there *appears* to be a violation of local conservation of
> energy -- by energy-flow mysteriously penetrating the boundary -- then we
> have a mystery of the highest order, the sort of paradox from which the
> great advances of physics come.  In particular, I cite
>  a) the discovery of cosmic rays, which was motivated by a
> barrier-penetration mystery of this sort, and
>  b) the discovery of neutrinos, ditto.

I teach my students that prediction of the existence of neutrinos
by Pauli is one of the greatest leaps of faith ever made by a true
believer, and that its vindication by Reines and Cowan two decades
later was very significant but not nearly so revolutionary. This is
just a more modern version of the leaps of faith made by Eudoxus
and Copernicus which were not vindicated until the eighteenth
century when James Bradley measured stellar aberration, by which
time heliocentrism was conventional doctrine anyway.

Our faith in physics is strong, but there are many misconceptions
yet to be expunged, and, no doubt, error remains even in the
orthodox paradigms. We have established ways of correcting the
latter problems; it is the former, the commonly established errors,
that are difficult to eliminate.

Leigh