Analysis of pre-service physics teachers’ mental models of and reasoning about the Higgs boson using the SOLO taxonomy

The Higgs boson, a cornerstone of the standard model, poses exceptional conceptual challenges for learners and future teachers due to its abstract, quantum-field nature. We conducted an interview study with 29 pre-service physics teachers who had completed an experimental particle physics course. The participants responded to eight targeted questions about the Higgs boson. Their answers were first analyzed qualitatively through the lens of the cognitive dimensions Fidelity of Gestalt and Functional Fidelity and were then coded according to the structure of the observed learning outcome (SOLO) taxonomy (pre-, uni-, multi-, relational). The results showed a dominance of dual thinking and pre-/uni-structural reasoning, with only a minority of relational responses indicative of integrated, expert-like reasoning. These patterns echo recent findings from physics education research and inform classroom practice.