The following student text on conservation laws, symmetries, and elementary particles was developed in a Dutch project for teaching modern physics to the top stream of the sixth year of secondary education (age 17–18). In a series of 35 lessons of 45–50 minutes each, students study particle-wave duality, the Heisenberg principle, probability models for properties of particles, the particle in a box, and applications, elementary particles, and astrophysics (http://www.phys.uu.nl/∼wwwpmn). In this paper we focus on particle physics and the key concepts of this chapter are: transformation, reaction equation, conservation laws, and symmetry. For recent literature regarding the teaching of symmetries and/or elementary particles, we refer to articles by Hill & Lederman,1 Pascolini & Pietroni,2 Kalmus,3 O'Connell,4 and Hanley.5

1.
C. T.
Hill
and
L. M.
Lederman
, “
Teaching symmetry in the introductory physics curriculum
,”
Phys. Teach.
38
,
348
353
(Sept.
2002
).
2.
A.
Pascolini
and
M.
Pietroni
, “
Feynman diagrams as metaphors: Borrowing the particle physicist's imagery for science communication purposes
,”
Phys. Educ.
37
(
4
),
324
328
(
2002
).
3.
P. I. P.
Kalmus
, “
Empty matter and the full physical vacuum
,”
Phys. Educ.
34
(
4
),
205
208
(
1999
).
4.
J.
O'Connell
, “
Comparison of the four fundamental interactions of physics
,”
Phys. Teach.
36
,
27
(Jan.
1998
).
5.
P.
Hanley
, “
Teaching particle physics
,”
Phys. Educ.
35
,
332
338
(
2000
).
6.
In advanced particle physics, physicists not only look at whether a reaction is possible, but also compute the probability that it takes place.
7.
Pair creation only takes place near heavy nuclei, which absorb part of the momentum of a photon. Otherwise there would be no simultaneous conservation of energy-mass and momentum. For example, consider a photon that has just enough energy to create the mass positron and an electron. If energy is just enough, then the photon has momentum but the positron and electron will be at rest. Momentum conservation in this reaction is only possible if a nucleus nearby absorbs the momentum of the photon. Therefore, pair creation cannot take place in vacuum.
8.
At extremely short distance, nuclear forces are repulsive to prevent collapse of the nucleus.
9.
See EPAPS Document No. E-PHTEAH-43-006505 for Appendix I.
This document may be retrieved via EPAPS homepage (http://www.aip.org/pubservs/epaps.html) or from ftp.aip.org in the directory epaps. See the epaps homepage for more information.
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