Welcome new faculty: Research Asst. Professor Seppe Kuehn

Siv Schwink

Seppe Kuehn is an experimental biological physicist who applies the tools of chemical and statistical physics to the study of ecology and evolution. His current research program at the Center for the Physics of Living Cells has two foci: first, to probe how ecosystems respond to well-defined environmental perturbations to uncover general statistical laws that govern behavior at the microscopic level; and second, to study evolution at the single-cell level by looking at how bacterial populations subjected to evolutionary pressures find nutrients in their environment. Kuehn’s approach to biological physics was shaped by colleagues at Rockefeller University, where Keuhn completed his postdoctoral work.

In the laboratory, Kuehn studies bacterial population dynamics and phenotypic evolution under controlled environmental conditions. His experiments will test long-held assumptions in ecology about how ecosystems respond to changes in their environment and the role adaptation plays in these responses. By making careful measurements with bacterial communities Kuehn and his collaborators hope to discover whether stability and adaptation in microbial communities are governed by general statistical laws.

“From physics, we learn that it can be powerful to describe a system’s macroscopic properties rather than each individual interaction,” explains Kuehn. “Think about the laws of thermodynamics, for example: first, we had laws that were inferred empirically from measurements, and though we couldn’t observe at the atomic level why these laws were true, they turned out to be incredibly powerful for understanding and controlling physical systems” explains Kuehn. “Biology is in many ways more complex, but maybe the approach is a valid one: within an ecosystem, you have organisms interacting in complex ways; by studying the emergent properties of the system, it may be possible to infer general laws about ecosystems that would have implications for understanding their dynamics. Such laws might even help us refine our understanding of how the organisms interact on the microscopic level.”

In a second postdoctoral project, Kuehn collaborated with a graduate student to develop high-throughput microscopy for studying microbial behavior, along with a new methodology for quantifying that behavior; using statistical approaches, he and colleagues discovered simple descriptions of immensely complex behavioral phenotypes. At Illinois Kuehn plans to extend these studies by looking at how microbial behaviors adapt under evolutionary pressures. These experiments will explore how behavioral phenotypes at the single-cell level emerge from genetic adaptions and how these adaptations drive variation across a population.

Kuehn received his bachelor’s degree in physics from Beloit College in 2000. He received his doctoral degree in chemical physics from Cornell University in 2007, working under John A. Marohn. Prior to his joining the faculty at Physics Illinois, Kuehn worked as a postdoctoral researcher at Rockefeller University in New York, under Stanislas Leibler in the Laboratory of Living Matter, Center for Studies in Physics and Biology (2007-2013). While there, he contributed to the development of holographic microscopes to obtain precise measurements of population dynamics in microbial communities. He and colleagues together hold a patent for the holographic device (2011).

Kuehn is the recipient of several honors, including a postdoctoral fellowship from the Helen Hay Whitney Foundation (2009-2012). He received a Tunis Wentink Award for Outstanding Doctoral Dissertation (2007) and a Wachter Prize for Excellence in Physical Chemistry (2005), each from the Department of Chemistry and Chemical Biology at Cornell University.

At Illinois, Kuehn is interested in developing a graduate course in quantitative biology with a curriculum that explores statistical physics and evolution using both theoretical and experimental methods. “Statistical tools are becoming increasingly important, especially in biological physics, where high throughput methods from sequencing to phenotyping are becoming standard,” comments Kuehn. “My goal will be to equip students with problem solving abilities and sound strategies for learning from these data and to pique their interest in the remarkable complexities of biological problems.”


Recent News

  • Research Funding

The United States Department of Energy awards $2.2 million to the FAIR Framework for Physics-Inspired Artificial Intelligence in High Energy Physics project, spearheaded by the National Center for Supercomputing Applications’ Center for Artificial Intelligence Innovation (CAII) and the University of Illinois at Urbana-Champaign. The primary focus of this project is to advance our understanding of the relationship between data and artificial intelligence (AI) models by exploring relationships among them through the development of FAIR (Findable, Accessible, Interoperable, and Reusable) frameworks. Using High Energy Physics (HEP) as the science driver, this project will develop a FAIR framework to advance our understanding of AI, provide new insights to apply AI techniques, and provide an environment where novel approaches to AI can be explored.

This project is an interdisciplinary, multi-department, and multi-institutional effort led by Eliu Huerta, principal investigator, director of the CAII, senior research scientist at NCSA, and faculty in Physics, Astronomy, Computational Science and Engineering and the Illinois Center for Advanced Studies of the Universe at UIUC. Alongside Huerta are co-PIs from Illinois: Zhizhen Zhao, assistant professor of Electrical & Computer Engineering and Coordinated Science Laboratory; Mark Neubauer, professor of physics, member of Illinois Center for Advanced Studies of the Universe, and faculty affiliate in ECE, NCSA, and the CAII; Volodymyr Kindratenko, co-director of the CAII, senior research scientist at NCSA, and faculty at ECE and Computer Science; Daniel S. Katz, assistant director of Scientific Software and Applications at NCSA, faculty in ECE, CS, and School of Information Sciences. In addition, the team is joined by co-PIs Roger Rusack, professor of physics at the University of Minnesota; Philip Harris, assistant professor of physics at MIT; and Javier Duarte, assistant professor in physics at UC San Diego.

  • Research

This year, 31 research teams have been awarded a combined 5.87 million node hours on the Summit supercomputer, the OLCF’s 200 petaflop IBM AC922 system. The research performed through the ALCC program this year will range from the impact of jets on offshore wind farms to the structure and states of quantum materials to the behavior of plasma within fusion reactors—all computationally intensive scientific applications necessitating the power of a large-scale supercomputer like Summit.

  • In Memoriam

Jim was widely viewed as one of the best teachers in the Physics Department. He was frequently listed in the University’s roster of excellent instructors and won awards for his classroom skills. In 2012, he received the Arnold T. Nordsieck Physics Award for Teaching Excellence for his “patient, insightful, and inspiring physics teaching, one problem at a time, that encourages undergraduate students to take their understanding to a new level.”

  • Research

Now a team of theoretical physicists at the Institute for Condensed Matter Theory (ICMT) in the Department of Physics at the University of Illinois at Urbana-Champaign, led by Illinois Physics Professor Philip Phillips, has for the first time exactly solved a representative model of the cuprate problem, the 1992 Hatsugai-Kohmoto (HK) model of a doped Mott insulator.