Three Upcoming Physics Seminar and Guest Lectures

The Physics Department will host the following upcoming events: 

The Accelerating Expanding Universe: Dark Matter, Dark Energy and Einstein's Cosmological Constant, Sept. 12

Bharat Ratra, PhD, distinguished professor of physics at Kansas State University, will be speaking at Creighton's Physics Department Seminar about "The Accelerating Expanding Universe: Dark Matter, Dark Energy and Einstein's Cosmological Constant." The event takes place on Thursday, Sept. 12, from 12:30 to 1:45 p.m. in the Hixson-Lied Science Building, Room G-59. Light refreshments will be provided.

Dark energy is the leading candidate for the mechanism that is responsible for causing the cosmological expansion to accelerate. Ratra will describe the astronomical data which persuade cosmologists that (as yet undetected) dark energy and dark matter are by far the main components of the energy budget of the universe at the present time. He will review how these observations have led to the development of a quantitative "standard" model of cosmology that describes the evolution of the universe from an early epoch of inflation to the complex hierarchy of structure seen today. In this nontechnical talk, he will also discuss the basic physics, and the history of ideas, on which this model is based.

Public Talk: Quantum Data Science? Sept. 19

David Meyer, PhD, professor of mathematics at the University of California, San Diego, will be giving a talk about "Quantum Data Science?" at a joint public seminar hosted by Creighton University's Department of Computer Science, Design, and Journalism; Department of Mathematics; and Department of Physics. The event takes place on Thursday, Sept. 19, from 12:30 to 1:45 p.m. in the Hixson-Lied Science Building, Room G-59. All are welcome, and light refreshments will be provided.

Quantum computing offers the possibility of efficient solutions to problems that may be classically intractable. Recently, these problems have included sampling from a probability distribution and inferring a relation from partial information (e.g., a recommender system), both of which fall into the class of data science or machine learning problems. An important characteristic of such problems and their solutions is the model for the data generating process, specifically whether it is classical or quantum. In the second part of the talk, we’ll analyze some data from a simple human behavior, answering survey questions, and discuss whether or not to model it quantum mechanically. He will (re)introduce all the quantum mechanics necessary for our analysis.

Information and Geometry in the Retina, Sept. 26

Alex Kunin, PhD, assistant professor of mathematics, will be speaking at Creighton's Physics Department Seminar about "Information and Geometry in the Retina," an interdisciplinary topic that combines neuroscience, mathematics and computer science. The event takes place on Thursday, Sept. 26, from 12:30 to 1:45 p.m. in the Hixson-Lied Science Building, Room G-59. All are welcome, and light refreshments will be provided.

The information we gather about the world through our senses is encoded and transmitted through the spiking activity of neurons. Viewed this way, the activity of a large set of neurons can be considered a joint probability distribution over a large number of binary states (namely, the spiking or silence of each neuron). A basic challenge of neuroscience is to find a parsimonious description of this distribution, and information theory offers a way to do so, called the Maximum Entropy Principle. In this talk, he will give a light introduction to information theory and (Shannon) entropy, explain the dominance of “low-order” correlations in the information content of the retina (aka, Why does the Ising model show up?), and offer an explanation by means of high school(ish) geometry. Along the way, he will muse about the role of network structure in all of this.