This project is part of an emerging research field called “active matter”. Researchers in this field focus on understanding the physics of systems that absorb energy from the environment and transform it into work. A typical example of an active system from nature is a cell. There are many molecular-scale motors in a cell, constantly transforming energy and working together to make the cell function in a certain way that makes life possible. The reason why it is so difficult to completely understand and predict the physics of cellular and living systems is that they are “out-of-equilibrium”, constantly transforming energy into motion. The field of active matter aims to tackle the challenge of understanding, modeling, and designing systems that possess the characteristics of being out of equilibrium.
A simple active system that scientists have designed is a small swimmer that converts energy input into motion, often referred to as “microswimmers”, or “active colloidal particles”. Even though the physics of active particles is much simpler than the physics of a cell, there are many unresolved questions in understanding their behavior. For example, if you place many particles together in a small petri dish filled with water, how do they affect each other’s motion? How does the behavior depend on the size and shape of the microswimmers? In this project, students anlyze this active collective motion using experimental data and modeling.