Theory of Confined Active Matter
The growing field of active matter studies the dynamics of systems comprised of many identical objects capable of autonomous motion. Examples include living systems such as bacterial colonies, ant swarms, animal flocks, and human crowds, to name a few. Confinements, which are ubiquitous in nature and experimental setups, can significantly influence the transport of living matter. Motile organisms inevitably bump into walls unless they use specific mechanisms to avoid them. This leads to a non-trivial coupling between the parts of an active matter system that accumulate at the walls and the parts moving in the bulk, that is, at some distance from the walls. The theory of confined active matter addresses particular questions such as: How do curvature and corners in confinement affect the distribution and dynamics of an active matter system? What is the most efficient way to computationally predict the transport of an active matter system in confined environments? These questions lead to intriguing mathematical problems involving differential geometry, differential equations, and stochastic processes.
"Boundary accumulations of active rods in microchannels with elliptical cross-section" (with C. Brown and S.D. Ryan), submitted (2024), [arXiv preprint] [supplementary videos]
"A kinetic approach to active rod dynamics in confined domains" (with L. Berlyand, P.-E. Jabin, and E. Ratajczyk), SIAM Multiscale Modeling and Simulation, Vol. 18, Issue 1, pp. 1-18 (2020) [arXiv preprint]
"Self-propulsion and shear flow align active particles in nozzles and channels" (with L. Dominguez Rubio, R. Baker, A. Sen, L. Berlyand, and I. Aranson), Advanced Intelligent Systems, Vol. 3, Issue 2, 2000178 (2020)
"Fight the Flow: The Role of Shear in Artificial Rheotaxis for Individual and Collective Motion" (with R. Baker, J. E. Kauffman, A. Laskar, O. Shklyaev, L. Dominguez-Rubio, H. Shum, Y. Cruz-Rivera, I. Aranson, A. C. Balazs, and A. Sen), Nanoscale, Vol. 11, pp. 10944-10951 (2019)
"Focusing of Active Particles in a Converging Flow" (with A. Kaiser, L. Berlyand, and I. Aranson), New Journal of Physics, Vol. 19, 115005 (2017) [arXiv preprint]