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Portland
Wednesday afternoon
the diagnostic. Our principal goal was preserving insights afforded by the
open-ended format while exploiting the logistical advantages of a multiple-
choice assessment. This new version explores the viability of a novel test
format where students select multiple responses and receive partial credit
based on the accuracy and consistency of their selections. Here, we present
the development, scoring, and preliminary analysis of the multiple-choice
CUE.
FB06:
1:20-1:30 p.m. Students’ Dynamic Geometric Reason-
ing About Quantum Spin-1/2 States
Contributed – Hunter G. Close, Texas State University-San Marcos, 601
University Drive, San Marcos, TX 78666;
Catherine C. Schiber, David Donnelly, Eleanor W. Close, Texas State
University-San Marcos
Quantum states are traditionally cognitively managed exclusively with al-
gebra rather than geometry. One reason for emphasizing algebra is the high
dimensionality of quantum mathematical systems; even spin-1/2 systems
require a 2-d complex number space for describing their quantum states,
which can be hard to visualize. Using “nested phasor diagrams,” which
use nesting to increase the dimensionality of graphic space, we taught
undergraduate students to represent spin-1/2 states graphically as well as
algebraically. In oral exams, students were asked to identify which spin-1/2
states, expressed numerically, would generate the same set of probabilities
as each other (i.e., they are the same except for a different overall phase fac-
tor). Video records of oral exams show that no students (N=13) performed
this task successfully using an algebraic method; instead, all students
solved the problem graphically. Furthermore, every student who succeeded
used a certain gesture to solve the problem.
FB07:
1:30-1:40 p.m. Effects of a Wave Function Manipulative
on Subsequent Student Gesturing
Contributed – Catherine C. Schiber, Texas State University-San Marcos, 601
University Drive, San Marcos, TX 78666;
Hunter G. Close, Eleanor W. Close, David Donnelly, Texas State University-
San Marcos
We compare student gestures from oral exams in an undergraduate
quantum mechanics course for two academic years, 2012 and 2013. In both
years, students were asked to show with their hands the quantum wave
function for various one-dimensional potentials by assigning the three
available spatial dimensions to the real part of the function, the imaginary
part of the function, and the scenario’s single spatial coordinate. In 2012,
the students’ instructor encouraged visualization of the wave function
in these terms by gesturing frequently and by explaining 2-d quantum
simulations in 3-d. In 2013, instruction included several in-class activities
involving building a 3-d representation of the quantum wave function
for several potentials using pipe cleaners. The oral exam in 2013 did not,
however, include the pipe cleaners. We present evidence of the influence of
the pipe cleaners on students’ cognitive management, including embodied
action, of the wave function.
FB08:
1:40-1:50 p.m. Teaching Undergraduate Quantum
Mechanics Courses: Contents, Textbooks, and Teaching
Methods
Contributed – Homeyra R. Sadaghiani, Cal Poly Pomona, 3801 W. Temple
Ave., Pomona, CA 91768;
Quantum mechanics suggests a new picture of physical systems that often
is in conflict with students’ classical views. For example, the underlying
principle of orthonormality of state vectors is not necessarily aligned with
student mental models of three- dimensional space vectors. Researchers
have found that these classical views can create barriers in student learning
of quantum concepts. Some researchers have postulated that introducing
quantum ideas in an unfamiliar context such as spin (that does not have a
classical counter part) might reduce the likelihoods of activating students’
classical resources. To test this, we have experimented with teaching quan-
tum mechanics using two different textbook approaches: (1) traditional
approach (starting with continuous basis); (2) spin first approach (starting
with discrete basis). We have investigated student learning of the core
concepts using classroom concept questions and end of quarter diagnostic
tests. We will discuss the implications of this study for choices of initial
context, the order and emphasis of content being taught, as well as how
Physics Education Research-based curriculum could be utilized to increase
student engagement and learning in these courses.
FB09:
1:50-2 p.m. Investigating Student Difficulties with
Measurements in Quantum Mechanics
Contributed – Gina Passante, University of Washington, Department of Phys-
ics, Seattle, WA 98195;
Paul Emigh, Peter S. Shaffer, University of Washington
The concept of measurement is a fundamental idea in quantum mechanics.
Ideas pertaining to quantum measurement have been shown to be difficult
for both introductory and advanced students. This is understandable, since
in learning quantum mechanics, students must successfully interpret a
new mathematical and conceptual formalism and recognize how this new
model differs from classical physics. We discuss some of the conceptual
and reasoning difficulties that we have identified related to measurement
in quantum mechanics, using illustrative examples from written and online
pretests and from post-tests administered on course examinations.
FB10:
2-2:10 p.m. Analysis of Faculty and Student Interviews
on Undergraduate Quantum Mechanics
Contributed – Christopher A. Oakley, Georgia State University, 400 Science
Annex, Atlanta, GA 30303;
Brian D. Thoms, Georgia State University
Characterizing faculty expectations is important to produce a compre-
hensive understanding of what knowledge students should acquire before
and during a quantum mechanics course (QMC). We analyzed interviews
conducted with faculty and students entering a QMC in the Department of
Physics & Astronomy at Georgia State University. The interviews examine
expectations regarding preparation, course material, and instructor’s goals
for a QMC. The goals of the interviews are to locate conflicts in perspective
and to provide students with a “map” for areas that will help strengthen the
knowledge and skills to be obtained before they enter a QMC. We report
on contradictions and similarities in perceptions from interview data de-
termined by coding the interviews and through the use of Activity Theory.
FB11:
2:10-2:20 p.m. Qualitative Understanding of Entropy
Changes in Upper-division Thermal Physics*
Contributed – Michael E. Loverude, California State University, Fullerton, De-
partment of Physics, MH-611, Fullerton, CA 92834;
Sissi L. Li, California State University, Fullerton
As part of an ongoing project involving research and curriculum develop-
ment in upper-division thermal physics, we have investigated student
understanding of the concept of entropy and the approach to thermal
equilibrium. Previous talks from this project have described student inter-
view responses concerning models of entropy in the approach to thermal
equilibrium and the quantitative connections between mathematical mod-
els of entropy that are macroscopic and particulate in nature. In the current
talk, we present data from written problems in which students are asked to
reason qualitatively about changes in entropy as well as about reversibility.
*Supported in part by NSF grants DUE 0817335 and 0817282.
