Professor Gerhard Gompper
Biological Information Processing
Forschungszentrum Juelich
Juelich, Germany

Thursday, April 22, 2021
11:00 am (CT)
Zoom webinar recording

Abstract

Active matter exhibits a wealth of emergent non-equilibrium behaviors [1,2]. A paradig-matic example is the interior of cells, where active components, such as the cytoskeleton,are responsible for its structural organization and the dynamics of the various components. Of particular interest are the properties of active polymers and laments [3,4]. The intimate coupling of active forces, thermal noise, hydrodynamic interactions, andpolymer connectivity implies the emergence of novel structural and dynamical features.Different propulsion mechanisms capture the physics of a variety of active polymeric systems, such as chains of active Brownian particles [3-5], polar laments propelled along their contours [6], or cytoskeletal polar laments propelled by motor proteins [7]. Thisleads to interesting single-particle behavior, such as a softening of a semiexible lamentof active Brownian particles at intermediate levels of activity [5], or a sperm-like beating motion of a lament pushing a load. At high polymer densities in two dimensions, collective dynamics characterized by active turbulence is observed [6].Vesicles (in three dimensions) [8] and closed polymer rings (in two-dimensions) [9] withinternal active components can be considered as highly simplifed models of cells. Here, theactive components lead to enhanced fluctuations [8] and an intimate coupling of propulsion forces, membrane deformability, cell shape, and cell sensing and reactivity [9]. In all these systems, computational models of active matter play an essential role to elucidate their non-equilibrium behavior [10]. [1] J. Elgeti, R.G. Winkler, and G. Gompper, Rep. Prog. Phys. 78, 056601 (2015). [2] G. Gompper et al., J. Phys. Condens. Matter 32, 193001 (2020). [3] R.G. Winkler, J. Elgeti, and G. Gompper, J. Phys. Soc. Japan 86, 101014 (2017). [4] R.G. Winkler and G. Gompper, J. Chem. Phys. 153, 040901 (2020). [5] T. Eisenstecken, G. Gompper, and R.G. Winkler, J. Chem. Phys. 146, 154903 (2017). [6]  O. Duman, R.E. Isele-Holder, J. Elgeti, and G. Gompper, Soft Matter 14, 4483 (2018).