The Reasoning of Quantum Mechanics

Horst R. Beyer

Marc L. Whiting, Lauren A. Barth-Cohen, Adrian L. Adams +2 more

The physics education research (PER) literature on quantum mechanics (QM) often acknowledges and minimizes what we refer to as the enigma of QM, viewing these aspects of QM as a challenge to overcome, rather than an inherent feature to be leveraged for learning. Using the overlapping theories of knowledge-in-pieces and resource theory as connected to an epistemological framing perspective, we focus on students’ descriptions of the enigma of QM and the epistemological frames that students view as relevant when approaching QM. Data comes from interviews with 10 undergraduate physics students who had learned quantum physics topics across different courses in the curriculum, ranging from sophomore-level modern physics to an advanced undergraduate-level QM course. To elicit students’ ideas on QM, the interview protocol emphasized their perspectives and empowerment when possible. Iterative rounds of qualitative analysis coded the data for how students described enigmatic aspects of QM, along with three epistemological frames students identified as their reasoning strategies: reasoning about scale, reasoning about the connections between QM and mathematics, and reasoning about the connections between QM and classical mechanics. The results document that students are aware that something about QM is unexplainable, an enigma to acknowledge. We argue that acknowledgment of the enigma of QM is a key part of what we refer to as thinking quantumly. Additionally, the epistemological frame of reasoning about scale has not been widely discussed in the QM-PER literature, which students use to distinguish QM from classical mechanics and to explain why mathematical models are needed. These results are important for amplifying students’ voices in how they approach enigmatic aspects of QM. Thus, our results begin to move the QM-PER literature beyond viewing enigmatic aspects of QM as obstacles to be corrected through refined instruction, toward an asset-based orientation as a source of meaningful insights for the learning process.

Mituo Taketani, Masayuki Nagasaki

Megan Wawro, John R. Thompson

Recognizing matrix equations as eigenequations or not: Examples of student reasoning in quantum mechanics

Hilary Putnam

Dennis Dieks

The thesis of this article is simple: even if it is accepted that quantum mechanics is a fundamentally probabilistic theory, this provides us with no special reason to believe in "chances" in the sense of objectively existing factors that are responsible for the relative frequencies we encounter in experiments.More in general, quantum mechanics gives us no special reason to believe in the actual existence of modalities.We may intuitively be inclined to believe in chances as a kind of causes, just as in classical mechanics we are inclined to think of forces as causal powers that produce accelerations.It might even be the case that intuitions of this kind can be developed into a coherent metaphysical scheme (something which has yet to be done, I think).But as I shall argue, a sober Humean perspective on quantum mechanics is certainly possible as well, and has much to recommend it.In short, the thesis of the present paper is that for a Humean, quantum mechanics introduces no reasons to abandon his position.