In discussing the important question of why physics understanding is so poor, Rustum Roy mentions the Annenberg Project video A Private Universe 1 and expresses his conclusion that “less than 10% of the American populace can handle any kind of abstraction” ( Physics Today, Physics Today 0031-9228 60 8 2007 10 https://doi.org/10.1063/1.2774081 August 2003, page 10 ). I also recommend the video, but for the opposite reason. After my first viewing, I felt about it as Roy does, but after additional viewings (including a very recent refresher), I suggest we consider the possibility that the culprit is inadequate teaching, not “incapable” students.
Perhaps the sharpest image that first-time viewers of the video come away with is ninth-grade Heather’s insistence that the light from the Sun in winter does not go directly to Earth but instead bounces toward Earth at a sharp angle, somewhere out in space. A private universe indeed!
The film should be viewed several times. Initially, Heather had had no instruction at all in astronomy. Before the second round of filming, she received instruction, including diagrams, on summer (light striking Earth at 90°, which, by the way, it never does at her northern latitude) and winter (light striking obliquely). Her teacher told her that in winter, the light is “indirect.” My guess is that the instructor, unfortunately, wanted to avoid using the word “oblique” as being too technical.
Almost anyone in our society knows what indirect lighting is. If the room you are in is illuminated by indirect lighting, you don’t see the source of the light at all; what you see is only light that has bounced off something at a sharp angle, and from there has proceeded to your eye (directly or indirectly). Heather is most likely just trying to integrate her correct understanding of indirect lighting with the instructor’s insistence that winter sunlight is indirect.
That exercise provides no support at all for the idea that Heather is incapable of handling abstraction. I urge that any such sweeping and consequential conclusion be established in a peer-reviewed education journal before it is otherwise disseminated to the physics community.
A fundamental reason why physics education is in such poor shape is typified by Michael Riordan’s Opinion piece in the same issue of Physics Today (page 50). Although I absolutely agree with Riordan’s insistence on experimental testing of theories, his emphasis on the nonexistent (in physics) distinction between things that are “real” and things that are purely “mathematical” is wrong. We know from quantum mechanics that nothing is real, except for the observations themselves.