Teaching quantum mechanics

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Quantum mechanics is a difficult subject to teach due to its counterintuitive nature. [1] As the subject is now offered by advanced secondary schools, educators have applied scientific methodology to the process of teaching quantum mechanics, in order to identify common misconceptions and ways of improving students' understanding.

Contents

Common learning difficulties

Students' misconceptions range from fully classical physics thinking, mixed models, to quasi-quantum ideas. [1] For example, if the concept that quantum mechanics does not describe a path for electrons or photons is misunderstood, students may believe that they follow specific trajectories (classical), or sinusoidal paths (mixes), or are simultaneously wave and particles (quasi-quantum: "in which students understand that quantum objects can behave as both particles and waves, but still have difficulty describing events in a nondeterministic way"). Among the concepts most often misunderstood are:

Issues also arise from misunderstanding classical concepts related to quantum concepts, such as the difference between light energy and light intensity.

Teaching strategies

Mathematics

Quantum mechanics can be taught with a focus on different interpretations, different models, or via mathematical techniques. Studies have shown that focus on non-mathematical concepts can lead to adequate understanding. [6]

Digital and multi-media

Despite the fundamental impossibility of directly viewing quantum states, multimedia visualizations are an important tool in education. Interactive media provides an alternative experience beyond everyday personal experience as a tool for understanding quantum mechanics. [2] Among the multimedia sites that have been studied with positive results are QuVis [7] and Phet. [8]

History and philosophy of science as educational guides

In introducing history as part of the process of teaching quantum mechanics sets up a potential conflict of goals: accurate history or pedagogical clarity. [9] Studies have shown that teaching through history helps students recognize that the counterintuitive issues are fundamental rather than simply something they don't understand. Specifically discussing the historical debates on quantum concepts drives home the idea the quantum differs from classical. [2] Discussing the philosophy of science introduces the idea that language derived from everyday experience limits our ability to describe quantum phenomena.

Directly discussing the meanings of words

Mohan [10] analyzes two widely used representative quantum mechanics textbooks against the learning challenges reported by Krijtenburg-Lewerissa [1] and others. Both texts adopt language ('waves' and 'particles') familiar to students in other contexts without directly exploring the significant shifts in meaning required by quantum mechanics. Mohan attributes some of the learning challenges to this unexplored application of inappropriate language.

Teaching for quantum computing

N. David Mermin reports that an unconventional strategy based on abstract but simple math concepts is sufficient to teach quantum mechanics to students interested in quantum computing application rather than physics. [11] Many of the issues that confound students of physics to not apply to this case and the mathematical background of quantum computing resembles the background already taught in computer science. Mermin develops notation and operations with classical bits then introduces quantum bits as superpositions of two classical states. He never needs to discuss even the Planck constant, which he suggests is important for quantum computer hardware but not software.

Teaching based on quantum optics

Philipp Blitzenbauer engages students through simple but intrinsically quantum single-photon experiments. [12] The approach avoids the ambiguous classical vs quantum character of photons in optical interference experiments like the double slit. Students exposed to quantum mechanics in this way avoid developing misconceptions apparent among students in the control group.

See also

Notes

  1. ↑ Whether the apparent nondeterminism of quantum mechanics is truly fundamental depends on the interpretation. [4] [5]

Related Research Articles

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<span class="mw-page-title-main">Double-slit experiment</span> Physics experiment, showing light and matter can be modelled by both waves and particles

In modern physics, the double-slit experiment demonstrates that light and matter can satisfy the seemingly incongruous classical definitions for both waves and particles. This ambiguity is considered evidence for the fundamentally probabilistic nature of quantum mechanics. This type of experiment was first performed by Thomas Young in 1801, as a demonstration of the wave behavior of visible light. In 1927, Davisson and Germer and, independently George Paget Thomson and his research student Alexander Reid demonstrated that electrons show the same behavior, which was later extended to atoms and molecules. Thomas Young's experiment with light was part of classical physics long before the development of quantum mechanics and the concept of wave–particle duality. He believed it demonstrated that Christiaan Huygens' wave theory of light was correct, and his experiment is sometimes referred to as Young's experiment or Young's slits.

<span class="mw-page-title-main">Quantum entanglement</span> Correlation between quantum systems

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References

  1. 1 2 3 4 Krijtenburg-Lewerissa, K.; Pol, H. J.; Brinkman, A.; van Joolingen, W. R. (2017-02-17). "Insights into teaching quantum mechanics in secondary and lower undergraduate education". Physical Review Physics Education Research. 13 (1): 010109. arXiv: 1701.01472 . doi:10.1103/PhysRevPhysEducRes.13.010109. ISSN   2469-9896. S2CID   13446988.
  2. 1 2 3 4 Bouchée, T.; de Putter - Smits, L.; Thurlings, M.; Pepin, B. (2022-07-03). "Towards a better understanding of conceptual difficulties in introductory quantum physics courses". Studies in Science Education. 58 (2): 183–202. doi: 10.1080/03057267.2021.1963579 . ISSN   0305-7267. S2CID   239272777.
  3. ↑ Marshman, Emily; Singh, Chandralekha (2017-03-01). "Investigating and improving student understanding of the probability distributions for measuring physical observables in quantum mechanics". European Journal of Physics . 38 (2): 025705. Bibcode:2017EJPh...38b5705M. doi: 10.1088/1361-6404/aa57d1 . ISSN   0143-0807. S2CID   126311599.
  4. ↑ Schlosshauer, Maximilian; Kofler, Johannes; Zeilinger, Anton (2013-08-01). "A snapshot of foundational attitudes toward quantum mechanics". Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics. 44 (3): 222–230. arXiv: 1301.1069 . Bibcode:2013SHPMP..44..222S. doi:10.1016/j.shpsb.2013.04.004. ISSN   1355-2198. S2CID   55537196.
  5. ↑ Schaffer, Kathryn; Barreto Lemos, Gabriela (24 May 2019). "Obliterating Thingness: An Introduction to the "What" and the "So What" of Quantum Physics". Foundations of Science . 26: 7–26. arXiv: 1908.07936 . doi:10.1007/s10699-019-09608-5. ISSN   1233-1821. S2CID   182656563.
  6. ↑ Dangur, Vered; Avargil, Shirly; Peskin, Uri; Dori, Yehudit Judy (2014). "Learning quantum chemistry via a visual-conceptual approach: students' bidirectional textual and visual understanding". Chem. Educ. Res. Pract. 15 (3): 297–310. doi:10.1039/C4RP00025K. ISSN   1109-4028.
  7. ↑ Kohnle, Antje; Cassettari, Donatella; Edwards, Tom J.; Ferguson, Callum; Gillies, Alastair D.; Hooley, Christopher A.; Korolkova, Natalia; Llama, Joseph; Sinclair, Bruce D. (2012-02-01). "A new multimedia resource for teaching quantum mechanics concepts". American Journal of Physics. 80 (2): 148–153. doi:10.1119/1.3657800. ISSN   0002-9505.
  8. ↑ McKagan, S. B.; Handley, W.; Perkins, K. K.; Wieman, C. E. (2009-01-01). "A research-based curriculum for teaching the photoelectric effect". American Journal of Physics. 77 (1): 87–94. arXiv: 0706.2165 . doi:10.1119/1.2978181. ISSN   0002-9505. S2CID   40164976.
  9. ↑ Kragh, Helge (1992-12-01). "A sense of history: History of science and the teaching of introductory quantum theory". Science and Education. 1 (4): 349–363. doi:10.1007/BF00430962. ISSN   0926-7220.
  10. ↑ Mohan, Ashwin Krishnan (June 2020). "Philosophical Standpoints of Textbooks in Quantum Mechanics". Science & Education. 29 (3): 549–569. doi:10.1007/s11191-020-00128-4. ISSN   0926-7220.
  11. ↑ Mermin, N. David (2003-01-01). "From Cbits to Qbits: Teaching computer scientists quantum mechanics". American Journal of Physics. 71 (1): 23–30. arXiv: quant-ph/0207118 . doi:10.1119/1.1522741. ISSN   0002-9505. S2CID   13068252.
  12. ↑ Bitzenbauer, Philipp (2021-07-22). "Effect of an introductory quantum physics course using experiments with heralded photons on preuniversity students' conceptions about quantum physics". Physical Review Physics Education Research. 17 (2): 020103. doi: 10.1103/PhysRevPhysEducRes.17.020103 . ISSN   2469-9896. S2CID   237715353.
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