Assumed Preparation: This is the easiest way to introduce
your students to two of the key concepts of quantum physics - wave-particle
duality and measurment-disturbance - through the double-slit experiment. This
is much clearer than the historical approach (blackbody radiation, photoelectric
effect, Compton effect) used by most textbooks. This lesson is based on a free
25-minute video and teachers guide from the Perimeter
Institute. It works best if students have already studied the wave model
of light and the experimental evidence for electrons. However, this is not essential
as it is reviewed in the video and activities. (If you prefer to cover the same
material without showing a video, you should use the quantum
interference lesson.)
Subversive Physics: This resource can be used even
if quantum physics is not in your curriculum - it can be included at the end
of a unit on the wave nature of light.
The Activities: You will need the free resource which
you can stream or order here.
You can spend one or many classes using this resource. If you only have one
class, I would reccomend that you do the Black Box demonstration (page 7), show
the video pausing between the chapters to discuss what is happening and then
use the concept questions (page 9) to generate discussions. Lots of focused
discussion is the best way to handle the counter-intuitive concepts of quantum
physics. I have taken the original fifteen concept questions given in the resource
and added another fourteen here.
Further Information:
If you want to delve further into the key concepts of quantum physics you should
next try the lesson on polarized
photons, which takes another wave property of light and re-examines it at
the quantum level. It also clearly demonstrates wave-particle duality and measurement-disturbance.
Iy also illustrates intrinsic randomness and entanglement. next, the lesson
on Heisenberg's Uncertainty Principle
looks at diffraction from a quantum perspective. Finally, the lesson on radioactivity
explores more deeply the effect of quantum physics on nuclear particles. These
'particles' show intrinsic randomness, uncertainty and wav-like behaviour including
tunneling.