Colloquia are held biweekly by the Saint Louis University Department of Physics on Thursdays at 4:10 p.m. to 4:50 p.m. through Zoom.
Using Superconducting Microwave Resonators as a Gamma Ray Detector
December 16, 2021
The Physics Colloquium Series presented David Wisbey, Ph.D. from SLU discussing “Using Superconducting Microwave Resonators as a Gamma Ray Detector” on Thursday December 16 at 4:10 p.m.
Superconducting microwave resonators are useful in several important applications including as single photon detectors in x-ray astronomy, memory elements in quantum information circuits, and as readouts of quantum bits, or qubits. They can easily be fabricated into large arrays with a unique frequency. At low power, the single photon regime, a microwave resonator can interact with materials quantum mechanically and can shed light on the current limits of quantum information. Because of their extreme sensitivity they can also be used to study the interaction of radiation, such as gamma rays, with matter. Dr Wisbey, with his graduate and undergraduate students, has worked both on improving materials for quantum information and the development of a new gamma ray detector. To improve materials for quantum information, our work has focused on improving surfaces and interfaces of materials. We also found that altering the surfaces of these materials affects their sensitivity to radiation.
GW170817: The Birth of Multi-Messenger Astronomy
December 02, 2021
The Physics Colloquium Series presented Greg Comer, Ph.D. from SLU discussing “GW170817: The Birth of Multi-Messenger Astronomy” on Thursday December 02 at 4:10 p.m.
In 2017, Multi-messenger astronomy/astrophysics finally arrived when gravitational waves were directly observed by the LIGO and VIRGO detectors. This event, known as GW170817, triggered a worldwide effort involving 70 observatories on 7 continents and in space to gather data across a wide band of electromagnetic radiation. With little doubt, GW170817 was produced by the inspiral and final merger of two neutron stars (the collapsed cores of regular stars which have exhausted their nuclear fuel). In fact, analysis of the GW170817 remnant contained the tell-tale signs of gold, as well as platinum, confirming nuclear physics predictions that the energetics of neutron star collisions can lead to natural production of the two elements. The interiors of neutron stars are natural laboratories for exploring extremes of many branches of fundamental physics — from elementary particle physics, through nuclear physics, to condensed matter physics, all within a context of gravitational fields so strong that general relativity must be employed. In this talk we will give an overview of the physics of neutron stars (implicitly motivating why multi-messenger astronomy is essential), and how a comprehensive approach to modeling the physics is being developed through the use of action principles.
Thrifty whales: Using the lowest drag and the highest inertia to save energy during migratory travel
November 04, 2021
The Physics Colloquium Series presented Jean Potvin, Ph.D., from SLU discussing “Thrifty whales: Using the lowest drag and the highest inertia to save energy during migratory travel” on Thursday November 04 at 4:10 p.m.
A few animals have been known to adopt energy-saving tactics during long distance travel. Here I present a new scenario of swimming gait that would cut-down metabolic costs in the large rorquals whales, such as the blue and humpback whales, which are known to travel yearly the thousands of miles across the oceanic basins separating their feedings and breeding ground. The results are based on drag data obtained from Computational Fluid Dynamics (CFD), Digital Particle Image Velocimetry (DPIV) and animal-borne sensor tags, all integrated into the well-known version of the Work-Energy Theorem discussed in introductory college physics.
A few questions: Possibly as topics for undergraduate research
October 21, 2021
The Physics Colloquium Series presented Dr. John James from SLU discussing “A few questions: Possibly as topics for undergraduate research” on Thursday October 21 at 4:10 p.m.
De-Mystifying Scientific Writing: Breaking Down the Basics
October 7, 2021
The Physics Colloquium Series presented Angela Mitchell from SLU Writing Services discussing “De-Mystifying Scientific Writing: Breaking Down the Basics” on Thursday, Oct. 7, at 4:10 p.m.
Scientific writing is not generally taught in high school or college-level composition courses, so its format and function can be intimidating for many undergraduate students. By keeping a clear focus on the topic and purpose of our research and findings, while also maintaining an awareness of our intended audience, we can produce clear, informative and engaging scientific papers. This workshop aims to break down the basic elements of scientific writing and explore techniques for producing papers that both inform our readers and provoke further discussion.
The Physics of Cancer
September 23, 2021
The Physics Colloquium Series presented Dr. Amina Mohammadalipour from Saint Louis University discussing “The Physics of Cancer” on Thursday, September 23, at 12:10 p.m.
The mechanical properties of cells are tightly correlated to many biological events, such as embryonic development, cell differentiation, aging, disease progression, and cancer metastasis. However, the interplay between cells’ deformability as well as the internal forces and their importance in cell signaling and fate have been insufficiently investigated. Dr. Alipour’s interdisciplinary research is centered upon the biophysical aspects of carcinogenesis from initiation and growth to progression and metastasis. New insights into the biophysical-driven cellular and subcellular functions, which critically regulate tumor invasion, will contribute to the development of drug discovery and therapeutic innovations.