Research Goal: to achieve a fine-grained analysis of in-the-moment student reasoning about quantum phenomena Particle Wave “Blob of EM wave” Non-localized Localized Interference pattern Dot on the screen Interferes with itself Flying through space Some localization, but “complicated to talk about where it is” Spreads out into interference pattern, and then dot on the screen Students revisit elements of the input spaces in order to “try on” new ideas Particle Wave “Blob of EM wave” Non-localized Localized Interference pattern Dot on the screen Interferes with itself Flying through space Some localization, but “complicated to talk about where it is” Spreads out into interference pattern, and then dot on the screen References [1] S. B. McKagan, K. K. Perkins, C. E. Weiman. PERC Proceedings 2006, pp , AIP Press (2006). [2] C. Baily, N. D. Finkelstein, arXiv: (2014). [3] G. Fauconnier and M. Turner, The Way We Think: Conceptual Blending and the Mind’s Hidden Complexities, Basic Books, [4] N. S. Podolefsky and N. D. Finkelstein, Phys. Rev. ST Phys. Educ. Res. 3, (2007). [5] A. Gupta, D. Hammer, E. Redish, J. Lrn. Sci. 19, 285 (2010). [6] M. T. H. Chi, J. Learn. Sci. 14, 161 (2005). Acknowledgements: The authors thank the CU PER group, our collaborators at the University of Maryland (Ayush Gupta, Andy Elby, Ben Dreyfus, Erin Sohr), and Doyle Woody. This work is supported by NSF TUES # ; views and findings presented are those of the authors. Understanding Blended Ontologies: A Case of Student Reasoning About Photons Jessica Hoy, Kathleen Hinko, Noah D. Finkelstein Department of Physics, University of Colorado Boulder WHAT IS A PHOTON? “A BLOB OF ELECTROMAGNETIC STUFF” Context Transformed Modern Physics for Engineers course [1,2]: focuses on the conceptual and applied nature, and physical interpretation of quantum phenomena Focus groups with students in this class 6 focus group sessions (spanning 12 weeks) A single photon is shot towards the slits and detected at the point shown on the screen. What is the most reasonable interpretation of where the photon was just before it was detected? a.It was located just in front of where it was detected b.It was spread out evenly in the space in front of the screen c.It was spread out in a non-even pattern in the space in front of the screen d.It was spread out evenly through all space Conceptual Blending Theory Fauconnier and Turner define mental spaces and the process by which they combine to create new meaning [3] Example: the Rutherford atomic model [4] Methods/Case Study The sim likely cues Eric’s use of the word “blob” Eric: it’s a big blob of…electromagnetic…stuff, instead of like a single point [gestures a small point with his hand] that’s like flying through space. And because of that it can interfere with itself and make the interference pattern. Tara: you can see it like as the photon, like it’s just this big blob of light, and it hits the screen, and there’s—it kind of spreads out into the interference pattern sort of [gestures fingers spreading out]. And so right before a dot appears, you can see, there’s like the [gestures horizontal lines]…spread out photon…mutters…makes sense. Eric: When you think of the photon as…like this blob of electromagnetic wave then, I think it becomes more complicated to talk about where it is, because, like, it’s an electromagnetic field…now, instead of like…a particle. Bryan: Yeah it’s weird to think that it’s like in more…places than one at a single time. Running the Blend (Elaboration) Conclusions Develop better understanding of how students reason about photons Demonstrate power of conceptual blending to map ontological negotiation Find evidence that ontologies are dynamic [5] and not fixed [6] Meaning Emerges for Students Tara: Well, I mean if you’re thinking of a photon as a wave that’s sort of spread out, it’s not like—it’s like, it’s spread out so if it doesn’t exist at a certain point it doesn’t mean it doesn’t exist at other points. Eric: Can you say that again? Tara: Like, you can have points where there is no energy from the photon, but you can have points where there is a lot of energy from the photon so overall, energy is conserved, it’s just uneven. 3 freshmen mechanical engineering majors: Bryan, Eric (white males), and Tara (unidentified female) * All names are pseudonyms Eric: …Like if you bounced a photon off of a wall, and then like halfway through the bounce it was like halfway over itself and it just canceled out to nothing— Bryan: Is that possible? Eric:—but then you can’t do that because of conservation of energy. Also, I’m not sure that photons bounce off walls Unproductive idea  students are unable to blend these two elements Solar system Atom Electrons revolve around nucleus Nucleus attracts electrons Planet revolves around sun Sun attracts planet Sun is yellow Electrons Nucleus Confined to atom Rutherford atom blend Want more?? Ask me about the fuzzy ball… WHAT IS AN ELECTRON? “A FUZZY BALL OF PROBABILITY” Contact: 0:00-1:25 1:25-2:10 2:10-2:35 Particle Wave “Blob of EM wave” Non-localized Localized Interference pattern Dot on the screen Interferes with itself Flying through space Some localization, but “complicated to talk about where it is” Spreads out into interference pattern, and then dot on the screen Energy is conserved, but uneven Energy distribution describes location of photon