All possible paths: bringing quantum electrodynamics to classrooms

Abstract

Quantum electrodynamics was described by Feynman as the ‘jewel of physics’ [1985 QED: The Strange Theory of Light and Matter (Alix G. Mautner Memorial Lectures) (Princeton, NJ: Princeton University Press)] because of its ability to precisely describe the interaction of light and matter. It embodies the key concepts of quantum physics and yet also describes classical optics. It is normally considered to be too advanced for use in schools. Here we show that through the use of novel learning tools called phasor wheels, it is possible to make quantum electrodynamics accessible to students from middle school and higher. Our graphical approach is based on the summation of all possible paths (formally known as Feynman path integrals). It uses graphical vector addition, and gives students a deep understanding of vectors. It offers insights into the quantum world in which observations represent quantum probability density, while correctly describing the laws of classical optics. The phasor wheel is a tactile tool that allows students to compute the probability of photons arriving at a point in space and to explore phenomena such as matter–wave interference, diffraction, and reflection without any distinction between quantum or classical. To make it accessible, we combine the phasor tool with real-life analogies, and videos of single quanta interference. Needing only elementary mathematics, the approach is suitable for middle/upper secondary schools as well early undergraduate students.

Interactive visualisation for teaching a quantum double slit experiment

“…In addition to this listing, three similar simulations [15, 16,17] showing electron interference were found. There were also found five teaching sequences aimed on the double slit experiment ( [18,19,20,21,22]), two of which used custom developed visualizations, which were not included in [13]. In the following, the visualization tools [14,23,15,16,17] found in the literature search are described and compared.…”

“…In the teaching sequences developed by Fanaro [19], and Choudhary and Blair [20], the Feynman path integral approach is used to describe interference and wave nature of quantum objects. Choudhary and Blair focus on explaining the basic optics phenomena (such as refraction or interference) by means of a hands-on activity with wheels, suitable even for middle school students.…”

Making an IMPRESSion: mapping out future directions in modern physics education

“…Today, teachers and educators embrace opportunities to teach modern physics topics in schools: they can choose from a growing number of learning resources, lesson plans, and professional development programmes (e.g. [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22]). These resources and programmes are often developed by education and public outreach teams of large-scale physics collaborations or institutes that connect cutting-edge physics with curriculum content.…”