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"quantization"



Well I'd say the mechanism of charge and mass quantization is =

"understood" and straightforward, i.e. the fact that fundamental =

particles exist. On the other hand, energy and angular momentum =

are quantized due to mysterious effects of QM. This is somewhat =

different, but even more interesting. The standard analogy is that
on a stairs height is quantized, which seems to apply to both cases =

about equally well. So those who believe every simplification is =

an oversimplification and will lead to an ineradicable misconception
in their students' minds should invent new term. Those of us who =

believe that physics, like life, is too complicated to get it all right =

on the first pass will continue to use one term and hope that our =

students get the more nuanced point on the next pass.

Incidentally I'm clearly missing something here. Why are they =

distinguishing between mass & matter quantization? Is
it the difference between atoms & quarks? =


KISS,
Bill Larson
Geneva


=3D=3D>In recently reading Halliday, Resnick, & Walker, I was alarmed to =
read
=3D=3D>"We have already seen that matter, energy and angular momentum are=

=3D=3D>quantized; [electric] charge adds one more important quantity to t=
he
list."
=3D=3D>Earlier in the book, one can find "Yet on a fine enough scale, air=
is
not
=3D=3D>continuous at all but comes in ... particles of specific masses ..=
=2E . =

We
=3D=3D>say that mass is quantized."
=3D=3D>
=3D=3D>This seems to me to be a very muddled idea of quantization. Consi=
der:
=3D=3D>- Mass is 'quantized' in the sense that it is made up of discrete
=3D=3D> particles. But as far as I know there is no way to index allowe=
d
masses,
=3D=3D> unless the system has only one atomic species.
=3D=3D>- Energy is 'quantized' in any *specific* system, and the allowed
energies
=3D=3D> can be indexed. However, for any energy you might choose, you c=
an
find a
=3D=3D> system in which that energy is allowed.
=3D=3D>- Charge is 'quantized' everywhere, always.
=3D=3D>
=3D=3D>Personally, of the three I would only say that "charge is quantize=
d",
since
=3D=3D>such a statement seems to imply some sort of universality. In a
particular
=3D=3D>system, I would say the energy is quantized *by the potential*. I=
would
=3D=3D>never say that mass is quantized; I would say that it is made up =
of
=3D=3D>particles. In any case, I *certainly* would never say "Charge is
=3D=3D>quantized, just like energy and mass;" those different cases aren=
't
very
=3D=3D>similar.
=3D=3D>
=3D=3D>How does everyone else feel about this. Am I expecting too much
precision
=3D=3D>in the language? Is there a deep, theoretical sense in which thes=
e
cases
=3D=3D>*are* similar? Or is this another entry for the text book
misconceptions
=3D=3D>list?