Students

Many useful documents, including a list of course prerequisites, are posted on the information page. Material relating to your particular program (BS, BA, 
Dual Degree, Pre-engineering) is also available, such as suggested curricula, Dual Degree worksheets etc.

The Physics Department offers a Bachelor of Science in Physics, a Bachelor of Arts in Physics, a Physics Minor, and Pre-engineering program. Each of these programs prepare students for success in a highly technological world.

Explore this web site to find out about the Physics faculty, programs, facilities, the projects and organizations physics students are involved in, and our colloquium series.

Physics Office: (660)785-4598, lindy@truman.edu 

We inducted three more members into Sigma Pi Sigma on March 4: Lauren Liegey, Katherine Maxwell, and Casey Wetzel.

Photos of department chair Ian Lindevald welcoming them into Sigma Pi Sigma:

Study of the Electronic Pairing Symmetry in Iron-Based Superconductors

Ryan T. Gordon
Department of Physics, Western Illinois University

The study of the symmetry of the wavefunction (order parameter) for electrons in newly discovered iron-based superconductors is one of crucial importance for understanding how this fascinating state of matter is possible in them. There are two experimental probes that are very useful for investigating the symmetry of the order parameter in a superconductor: the London penetration depth and the thermal conductivity. The London penetration depth characterizes how externally applied magnetic fields are screened from a superconductor and it can be measured with remarkable sensitivity. The thermal conductivity, which is a measure of how efficiently materials can transport heat, can tell us how much entropy is available from normal state electrons in the limit of absolute zero temperature. In my talk, I will show data from both London penetration depth and thermal conductivity experiments on iron-based superconductors and outline in detail what we have concluded about the symmetry of the superconducting order parameter in the iron-based superconductors.

Level: Intermediate

Young Star Clusters and the Initial Mass Function

Bruce Wilking
Department of Physics and Astronomy, University of Missouri—St Louis

The distributions of stellar masses, or Initial Mass Functions (IMFs), in the disk of our Galaxy and in visible star clusters are remarkably similar. But subtle differences do exist and must trace back to the star formation process. By investigating the distribution of stellar masses in young star clusters still associated with molecular clouds, one can hope to connect differences in the IMFs with the physical conditions of the gas from which they formed. I will describe a spectroscopic survey of the young Rho Ophiuchi cluster and a comparison of its IMF with that of other young clusters.

Level: Intermediate

Magnetic field effects in organic semiconductors: from touch screen displays to bird navigation

Markus Wohlgenannt
Department of Physics and Astronomy, University of Iowa

Organic semiconductors are electrically conducting plastic materials, whose main applications are as display pixels as well as plastic solar cells. We show that these materials are however also promising as magnetic field sensors, similar to read-heads used in computer hard disk drives. We propose a novel application, combining the display pixel property with the magntoresistive property to construct a pen-input touch screen display. We will briefly discuss the physics that underlies the magnetic field effects. Interestingly, it has been proposed that a very similar mechanism is used by birds to navigate during migration season.

Level: Intermediate

Neural Networks vs. Self-Consistent Field Equations In Ab Initio Simulations

Paul Rulis
Department of Physics and Astronomy, University of Missouri – Kansas City

This presentation presents an exploration of an alternate method for calculating accurate total energies of complex defect containing solids that is based on machine learning. Within the ab initio orthogonalized linear combination of atomic orbitals (OLCAO) method for electronic structure calculation the solid state potential function is expanded as a summation of atom centered Gaussian functions. The coefficients of these functions are normally determined through self-consistent field iterations applied to the whole system. However, for large and complex systems where many atoms have substantially different local geometries this approach becomes excessively burdensome. A new approach to obtaining the potential function coefficients and subsequently computing the total energy is under development. Progress of the method development as applied to a passive defect model in silicon, a self-interstitial model in silicon, and a model of amorphous silicon will be presented.

Level: Advanced

Our own Women in Physics organization was prominently featured on the front page of November 28′s Kirksville Daily Express, due to a demonstration event they performed at the Adair County Public Library. (Story / Photos)

Investigating interfacial phenomena at the micro/nanoscale to enhance engineering of surfaces

Sriram Sundararajan
Department of Mechanical Engineering, Iowa State University

Engineering research aims to study various phenomena of interest with the aim of leveraging the understanding gained in realizing technological solutions for a given need. Mechanical engineering research broadly addresses phenomena associated with forces and energy. This talk will introduce you to the research that is conducted in the Mechanical Engineering program at Iowa State University. Next, projects involving scanning probe microscopy to study interfacial phenomena such as nanoscale friction, molecular force interactions and atom-scale assessment of material transfer will be illustrated. Finally the talk will conclude with information regarding the Mechanical Engineering Graduate Program at Iowa State University.

Level: Introductory

Brief Speaker Bio: Sriram Sundararajan is an Associate Professor of Mechanical Engineering at Iowa State University. He received a B.E. degree in Mechanical Engineering from The Birla Institute of Technology and Science, Pilani (India) in 1995 followed by M.S. and PhD degrees in Mechanical Engineering from The Ohio State University, Columbus, OH in 1997 and 2001, respectively. His research areas encompass multiscale tribology (friction, wear and lubrication), surface patterning and surface engineering. He has authored over fifty peer-reviewed journal articles and conference presentations and has obtained over $2 Million in research grants from federal and state agencies, private foundations and industry. He was also a recipient of a Miller Faculty Fellowship at Iowa State for innovations in teaching and curricular development.

Circuits Of Vision: Dynamics Of Seeing

Ralf Wessel
Department of Physics, Washington University, St. Louis

Arguably the biggest goal of modern neuroscience is to gain a deeper and more complete understanding of strongly correlated neural systems, also known as microcircuits. A striking phenomenon of strongly correlated neural systems is visual perception, where a convincing microscopic theory remains elusive. The challenges posed by visual perception clearly highlight the need for fresh concepts. One step towards attaining this goal is to understand evolutionary related but reduced versions of microcircuits in visual pathways.

I will present results from our research on visual pathways in reptiles and birds. These pathways provide useful model preparations in which to realize accessible and anatomically well-defined microcircuits exhibiting the processing of visual information. The microcircuits allow the control over experimental variables such as the visual stimuli, the cellular properties, and the neural interaction. The possibilities afforded by reptile and bird visual pathways substantially widen the scope of relevant brain models, the solutions of which can often have surprising and unexpected properties.

Level: Intermediate

Mathematical God, Heavenly Physics

Ronald Bieniek
Department of Physics, Missouri University of Science and Technology

For two and a half millennia, the mode and direction of inquiry into the physical world has been strongly influenced by visions of a rational, mathematical God. Much of this can be traced to the discovery by Pythagoras of the mathematical basis of musical harmony, and to the observed regularity of celestial motions. Later neo-Platonism, particularly its religious elements, directly affected the astronomical ideas and arguments of Copernicus, Kepler, and Descartes. Although it might superficially appear that mathematical mysticism was washed away from theoretical physics and astronomy by Galileo and Newton, the undercurrent of traditions remained, even though the sources might be denied or unseen. Modern particle physics, with its stress on symmetries, is an example of the continuing strength of this current. The cosmic beauty of the Mathematical God is still with us

Level: Introductory

Computer Simulations of the Biomechanics and Hydrodynamics of Lunge Feeding by Rorqual Whales – A Physicist’s Explorations Into the World of Zoology

Jean Potvin
Department of Physics, Saint Louis University

Lunge feeding is a strategy employed by rorqual whales (such as the blue and humpback whales) to catch in only one gulp a large amount of krill and other small fish that swim in schools. A lunge consists in a whale accelerating towards its target, and then swiftly opening its mouth to allow-in a large amount of water and prey. The lunge ends with the closing of the mouth and the filtering of the engulfed water out of the buccal cavity through the whale’s baleen plates. The filling process that expands the initially folded, highly-extensible and compliant buccal cavity blubber shares a lot of commonalities with the unsteady fluid dynamics of parachute inflation. But there are crucial differences as well, including the use of ventral muscle contraction to gradually push forward the engulfed water (and prey) and reduce the hydrodynamic loads on the body.

This presentation will show how a simple analysis of the forces applied on the whale-ocean system can be used to reveal important information on the kinematics and energetics of lunge feeding, including tantalizing details on the physical limits on the largest body size attainable by whales. We will show also how today’s state-of-the-art digital tagging technology is applied to track the motion of whales in their environment and how such data is used for modeling validation.

(Latest paper on subject.)

Level: Intermediate