Supporting Pre-Service Primary School Teachers with Hands-on-Science

The education that primary school students receive shapes their relationship with science. Elementary school teachers report they have low confidence and enthusiasm about teaching science. The Hands-on-Science Program at UT Austin was created to serve the unique needs of Applied Learning and Development majors. HoS consists of four required content courses: Physics, Chemistry & Geology, Biology, and Astronomy & Earth Climate. HoS classes differ from traditional science courses in two ways: (1) method of instruction, and (2) content. Our students attain higher learning gains and display improved attitudes towards learning science, compared to students who take traditional science classes

Relaxation Phenomena in a System of Two Harmonic Oscillators

We study the process by which quantum correlations are created when an interaction Hamiltonian is repeatedly applied to a system of two harmonic oscillators for some characteristic time interval. We show that, for the case where the oscillator frequencies are equal, the initial Maxwell-Boltzmann distributions of the uncoupled parts evolve to a new equilibrium Maxwell-Boltzmann distribution through a series of transient Maxwell-Boltzmann distributions. Further, we discuss why the equilibrium reached when the two oscillator frequencies are unequal, is not a thermal one. All the calculations are exact and the results are obtained through an iterative process, without using perturbation theory.Comment: 22 pages, 6 Figures, Added contents, to appear in PR

Relaxation in harmonic oscillator systems and wave propagation in negative index materials

textThis dissertation is divided up into two parts, each examining a distinct theme. The rst part of our work concerns itself with open quantum systems and the relaxation phenomena arising from the repeated application of an interaction Hamiltonian on systems composed of quantum harmonic oscillators. For the second part of our work, we shift gears and investigate the wave propagation in left-handed media, or materials with simultaneously negative electric permeability and magnetic permeability . Each of these two parts is complete within its own context. In the rst part of this dissertation, we introduce a relaxation-generating model which we use to study the process by which quantum correlations are created when an interaction Hamiltonian is repeatedly applied to bipartite harmonic oscillator systems for some characteristic time interval . The two important time scales which enter our results are discussed in detail. We show that the relaxation time obtained by the application of this repeated interaction scheme is proportional to both the strength of interaction and to the characteristic time interval . Through discussing the implications of our model, we show that, for the case where the oscillator frequencies are equal, the initial Maxwell-Boltzmann distributions of the uncoupled parts evolve to a new Maxwell-Boltzmann distribution through a series of transient Maxwell-Boltzmann distributions, or quasi-stationary, non-equilibrium states. We further analyze the case in which the two oscillator frequencies are unequal and show how the application of the same model leads to a non-thermal steady state. The calculations are exact and the results are obtained through an iterative process, without using perturbation theory. In the second part of this dissertation, we examine the response of a plane wave incident on a at surface of a left-handed material, a medium characterized by simultaneously negative electric permittivity and magnetic permeability . We do this by solving Maxwell's equations explicitly. In the literature up to date, it has been assumed that negative refractive materials are necessarily frequency dispersive. We propose an alternative to this assumption by suggesting that the requirement of positive energy density can be relaxed, and discuss the implications of such a proposal. More speci cally, we show that once negative energy solutions are accepted, the requirement for frequency dispersion is no longer needed. We further argue that, for the purposes of discussing left-handed materials, the use of group velocity as the physically signi cant quantity is misleading, and suggest that any discussion involving it should be carefully reconsidered.Physic

Hands-on-Science: Using Education Research to Construct Learner-Centered Classes

Research into the process of learning, and learning astronomy, can be informative for the development of a course. Students are better able to incorporate and make sense of new ideas when they are aware of their own prior knowledge (Resnick et al. 1989; Confrey 1990), have the opportunity to develop explanations from their own experience in their own words (McDermott 1991; Prather et al. 2004), and benefit from peer instruction (Mazur 1997; Green 2003). Students in astronomy courses often have difficulty understanding many different concepts as a result of difficulties with spatial reasoning and a sense of scale. The Hands-on-Science program at UT Austin incorporates these research-based results into four guided-inquiry, integrated science courses (50 students each). They are aimed at pre-service K–5 teachers but are open to other majors as well. We find that Hands-on-Science students not only attain more favorable changes in attitude towards science, but they also outperform students in traditional lecture courses in content gains. Workshop Outcomes: Participants experienced a research-based, guided-inquiry lesson about the motion of objects in the sky and discussed the research methodology for assessing students in such a course