Re: heat is a form of energy

[Leigh Palmer <palmer@SFU.CA>]

I have added footnotes to what follows. It is the best question I've
had to answer, and I would like to separate the parenthetical comments
that are my inevitable style from the mainstream of the discussion.
The footnotes are only important from my point of view; they probably
only annoy the casual reader. Thanks, Bob, for letting me discuss what
I think is really important.

At 21:12 -0700 9/9/99, Bob Sciamanda wrote:

> Leigh,
> I am puzzled by your ascribing "substantiality", the ability to "flow",
> etc. to both atoms and electric charge.  Your reason seems to be that both
> are "locally conserved". (Perhaps I misread you - please correct me.)

That is exactly what I meant(1).

> It is not apparent to me why this should be the criterion of
> "substantiality", the ability to "flow", etc., or indeed just what
> "locally conserved" means here.

My first criterion for recognizing substance is that all observers
should agree on where the substance is and how much of it is there.
This is the criterion of locality(2).

Consider a system consisting of two similar electrically charged
automobiles approaching one another at high speed in a vacuum. The
number of stable atoms in car 1 is N1, the number in car 2 is N2.
Similarly, the charge on car 1 is Q1 and the charge on car 2 is Q2.
The kinetic energies of the cars are, respectively, K1 and K2. We
will neglect all other energies for purposes of this discussion.

All observers would agree on the number of atoms in each car and
on the charge borne by each car; accelerated observers would do so
as well. Consider the kinetic energies, however. In two inertial
frames of reference observers would ascribe a zero value to one or
the other of K1 and K2. That is about as insubstantial a quantity
as I can imagine.

> Atoms can transmute and even conceivably disappear, leaving only a myriad
> of particles or only radiation.

I knew they could transmute; I didn't know they could disappear.
In either event, however, I believe that other conservation laws
were in effect, e.g. conservation of baryon number, lepton number,
... In order that we not confuse the situation let us neglect any
problems associated with radioactive contaminants in the autos.

> Charge is only conserved as an algebraic sum, after counting some as
> "positive" and others as "negative" (we might have labeled them "green"
> and blue").  Is "substance" created (destroyed) in the process of pair
> production (positron-electron annihilation)?  Is there a "negative
> substantiality"?

Yes, there is negative substance to electric charge, as you
observe. Total electric charge is the sum of all charges with
signs taken into account.

> I am not being argumentative; I truly seek to follow your thinking,
> especially your adamant dogmatization about viewpoints which seem to be
> only conceptually or "philosophically", and not empirically or
> mathematically, divergent.  Down this road lies religious wrangling, not
> science.

I'm sorry you feel that way. The science is much easier to
understand when misconceptions (especially unnecessary ones) are
exposed and eliminated. There is no need to view energy as being
substantial. It does not make Nature easier to understand for
most of the sophisticated folks in this group. They just don't
yet know that.

Physics holds no truths about Nature. The best we can do is to
construct our best descriptions of Nature, their goodness being
judged by their accuracy and elegance. Substantial energy is, to
say the least, inelegant. I have high school teachers asking me
if photons are pure energy. How do I answer such a question?
Most of them don't know what a photon is (I'm not sure I could
tell them) and if I tell them there's no such thing as "pure
energy" they just don't seem to want to hear me.

If you see my position as that of a member of a religious
minority then I can accept that; I've never been a member of a
majority. However, if I can convert you, I can promise you will
see The Light.

Religious enough for you?

Leigh

(1) Language is very important to me. The word "substantiality" in
the question is a strange construction. It should be replaced by
the word "substance", in which case the quotation marks should be
omitted. The problem seems to be that I used the good old English
word "substantial" instead of the modern, ugly "substantive" that
seems to be replacing it in politically correct Newspeak.

(2) If you want a bigger word use "localizability".