Theoretical Physics of Complex Systems
Group leaders:
Prof. dr. Fred MacKintosh and Dr. Greg Stephens

Prof. dr. Fred MacKintosh 

Our research interests concern the fundamental physics of soft matter, of which biological materials are principal examples. While our understanding of the single-molecule properties of many of the key building blocks of the cell is relatively advanced, our understanding of the basic physics governing biological assemblies from the nanometer to the micrometer scales is, by comparison, still rudimentary. Many sub-cellular structures involve the coordinated assembly of disparate elements such as soft membranes and stiff filamentous proteins. Our specific research interests include the structural, mechanical and dynamic properties of these and other soft materials.

Contact: Prof. dr. Fred MacKintosh, email:


Dr. Greg Stephens

The physics of living behavior

Working at the interface of physics and biology, our group explores a diverse set of problems ranging from the motion of small organisms to the dynamics of human cognition.  We leverage cross-disciplinary experimental collaborations to combine novel measurements with theoretical principles drawn from statistical physics, information theory and dynamical systems. In the natural wiggling of the roundworm C. elegans we derived a low-dimensional but complete basis of worm shape (eigenworms) which we are exploiting to construct a systems biophysics on the scale of an entire multi-cellular organism. In human neuroscience, we developed a computational approach based on the coupled neural dynamics of multiple brains engaged in natural communication.  In all of our efforts, unlike traditional approaches that restrict behavior or it’s neural correlates from the outset, we use the variation of biological systems under natural conditions to search directly in the data for simple, functional understanding.

Contact: Dr. Greg Stephens, email 


A possible bachelor project: Is the information content of transcription factors sufficient to regulate gene expression in various organisms?