NBIA Colloquium via Zoom by Ramin Golestanian (Max Planck Institute)

How living matter self-organizes while breaking action-reaction symmetry

Speaker: Ramin Golestanian (Max Planck Institute)

Abstract: Cells and microorganisms produce and consume all sorts of chemicals, from nutrients to signalling molecules. The same happens at the nanoscale inside cells themselves, where enzymes catalyze the production and consumption of the chemicals needed for life. In this colloquium, I will discuss a generic mechanism by which such chemically-active particles, be it cells or enzymes or engineered synthetic colloids, can "sense" each other and ultimately self-organize in a multitude of ways. A peculiarity of these chemical-mediated interactions is that they break action-reaction symmetry: for example, one particle may be repelled from a second particle, which is in turn attracted to the first one, so that it ends up "chasing" it. Such chasing interactions allow for the formation of large clusters of particles that "swim" autonomously. Regarding enzymes, we find that they can spontaneously aggregate into clusters with precisely the right composition, so that the product of one enzyme is passed on, without lack or excess, to the next enzyme in the metabolic cascade.

Brief bio-sketch: Ramin Golestanian obtained his BSc from Sharif University of Technology in Tehran, and his MSc and PhD from the Institute for Advanced Studies in Basic Sciences (IASBS) in Zanjan. His PhD work was conducted under the remote supervision of Mehran Kardar from MIT, and was followed by an independent postdoctoral research fellowship at the Kavli Institute for Theoretical Physics at the University of California at Santa Barbara. He has held academic positions at IASBS, the University of Sheffield, and Oxford University, and risen through the ranks until he became a Full Professor in 2007. He has a broad interest in various aspects of non-equilibrium statistical physics, soft matter, and biological physics. Golestanian is distinguished for his work on active matter, and  in particular, for his role in developing microscopic swimmers and active colloids. Ramin Golestanian is elected Fellow of the American Physical Society and the Institute of Physics, and recipient of the Holweck Medal of the Société Française de Physique and the Institute of Physics, EPJE Pierre-Gilles de Gennes Lecture Prize, Martin Gutzwiller Fellowship of the MPI-PKS, Nakamura Lecturer Award of UCSB, and 50th-Anniversary Most Distinguished Alumni Award of Sharif University of Technology.

To participate on Friday, click on

https://ucph-ku.zoom.us/j/61333932427 

The colloquium will be introduced and moderated by Amin Doostmohammadi and we strongly encourage you to participate actively by asking questions during the talk. Amin will briefly remind you how this can be done just before the colloquium starts.