What Is Light?

Abstract

Quantum physics describes light as having both particle and wave properties; however, there is no consensus about how to interpret this duality on an ontological level. This article explores how preuniversity physics students, while working with learning material focusing on historical-philosophical aspects of quantum physics, interpreted the wave-particle duality of light and which views they expressed on the nature of physics. A thematic analysis was performed on 133 written responses about the nature of light, given in the beginning of the teaching sequence, and 55 audio-recorded small-group discussions addressing the wave-particle duality, given later in the sequence. Most students initially expressed a wave and particle view of light, but some of these gave an "uncritical duality description", accepting without question the two ontologically different descriptions of light. In the small-group discussions, students expressed more nuanced views. Many tried to reconcile the two descriptions using semi-classical reasoning; others entered into philosophical discussions about the status of the current scientific description of light and expected science to come up with a better model. Some found the wave description of light particularly challenging and lacked a conception of "what is waving". Many seemed to implicitly take a realist view on the description of physical phenomena, contrary to the Copenhagen interpretation which is prevalent in textbooks. Results are discussed in light of different interpretations of quantum physics, and we conclude by arguing for a historical-philosophical perspective as an entry point for upper secondary physics students to explore the development and interpretation of quantum physical concepts.

Pre-Service Teachers’ Declarative Knowledge of Wave-Particle Dualism of Electrons and Photons: Finding Lexicons by Using Network Analysis

“…Second, it demands an epistemological shift (i.e., change in our conceptions of the justification of our knowledge claims) regarding causal determination and the probabilistic determination of events [1,2,6]. The research concerning learning wave-particle dualism has recently been comprehensively summarized in studies by [1][2][3]6] whose main findings are not reiterated here; only the aspects relevant to the present study will be discussed in what follows.…”

“…Recent science education research has placed a lot of attention on learning the wave-particle dualism of quantum entities [1][2][3][4][5]. This is partly due to the central role of wave-particle dualism in learning quantum physics, but also because it concerns the very basic phenomenon of how a learner constructs mental models of a new ontological category (i.e., categories of existing entities) in the absence of direct perceptions or experiences of that category.…”

“…Research on learning wave-particle dualism, or more generally, on learning quantum physics, has focused on discovering students' mental models, which are taken as structures of mind that allow cognitive simulation of reality, for example in making predictions, providing explanations and evaluating outcomes [1][2][3]. Many research approaches attempt to reveal students' mental models using interviews and their interpretative analysis (see e.g., [1] for detailed discussions).…”

Analysis of secondary school quantum physics curricula of 15 different countries: Different perspectives on a challenging topic

“…(p. 31) and "The students explain that the wave-particle dualism is abolished by the probability interpretation" (p. 45). The Norwegian curriculum document emphasizes the qualitative description of quantum phenomena and requires students to be able to discuss philosophical and epistemological aspects of NOS [77]. For educational research, it would be interesting to examine how teaching different interpretations affects students' understanding of QP and NOS.…”

“…A focus on atomic QP connects the content of chemistry and physics. Including the wave function, or other mathematical descriptions resembles the traditional introduction of QP at university level and could serve as an orientation on this, whereas a philosophical focus facilitates discussing the NOS [77]. Different foci thus reflect what Osborn and Dillon call the dual mandate of science education: serving "the needs of future scientists and the need of the future non-scientists."…”