Re: historical physics (a bit on the long side - sorry)

[Allen Brown <brownan@educ.queensu.ca>]

On Mon, 22 Jul 1996, Paul Camp wrote:

> Just curious -- does this program include consideration of alternate 
> ideas that turned out not to work or of alternate formulations 
> abandoned since they are less convenient? There is a nifty example of 
> the latter in Galileo's choice of definition for acceleration (which 
> I believe is in the Dialogues). The thing I always liked about 
> Burke's Connections series is the explicit recognition that the 
> development of scientific ideas is generally a great deal more 
> chaotic than the histories usually depict.

Well, I think that we might have done better.  We do spend some time 
with Aristotelian, Ptolemaic, Aristarchan, Copernican, Tychonic, and 
Keplerian models, trying to help students understand the assumptions that 
underpin them, and what objections led to abandonment, modification, and 
so on.  Further, we are trying to get students to think about issues of 
simplicity and predictability of models.  So, they do see some of the 
blind alleys that were not so blind to the people who advanced those ideas.

We're less successful at exploiting the faltering steps in mechanical 
determinism, but we do want students to know that even Newton had some 
misconceptions, for example, about the central force requirements of 
planetary motion (it was one of his rivals, Hooke, that originally 
proposed some kind of central force suggestion, while Newton was still 
thinking about planets being dragged around, I believe).  And, we want 
students to get some idea of the staggering leap made by Newton to 
associate motions near the Earth with those in the heavens.  Finally, we 
hoe that they will appreciate the difference between a description of a 
phenomenon and an "explanation" of the phenomenon, and, of course, the 
importance of mathematics as a descriptive tool.

With the energy concept we want them to have a really hard look at
phlogiston / caloric theory, and to try to poke holes in it.  Then, we
want them to trace the development of the energy concept based on the
practical applications of thermodynamics - steam engines - coupled with
the theoretical understanding that arose by studying these machines.  The
section ends by asking students to consider carefully the idea of energy
as an abstraction - I know that we've had these discussions before here -
sorry. 

For the quantum concept we have them try to explain the PE effect using
the wave theory of light.  And we want them to differentiate between
Planck's notion of the quantization of the radiators with Einstein's
quantization of the radiation field.  Then, sadly, owing to the lack of
mathematical sophistry that limits us, we try (but probably fail) to do
justice to the de Broglie and Shrodinger hypotheses and formulations,
ending with a review of the role of abstract mathematical theory in
describing nature. 

For the Higher Level students, they also examine the development of the 
entropy concept (an extension of the material on the energy concept), 
including Maxwell's demon, and the necessity of using both First and 
Second Laws in the analysis of system energy.  They also extend the 
quantum concept with a more detailed analysis of the UV catastrophe and 
Planck's modifications to the energy per oscillator to overcome the 
problem.  Finally, they do some study of conservation principles and 
symmetry (on a pretty qualitative scale, I admit) in which they consider 
such topics as virtual exchange particles, conservation laws for nuclear 
processes (including lepton, muon, and baryon numbers), they use the 
eightfold way to predict the existence of the omega minus, and describe 
and apply simple quark theory (qualitative), culminating in a 
consideration of the role of organizing principles in science.

I know, I know.  This is all pretty ambitious.  We thought it was worth 
the effort to have students step back a bit from nitty gritty "bread and 
butter" physics to consider both what the really big issues are, and 
their development over time.

We will see how it all comes out.  The syllabus will begin to be taught 
this September.  I can say that many schools seem to be very interested 
in teaching this option.

As always, it would be interesting to hear comments from people on this 
list.  And, as always, I have a pretty thick skin and am not easily offended.


Allen