News: Scientists have found a clue to the dynamic origin of fluctuations in systems like fish schools, swarms of insects, flocking birds and bacterial colonies. These are called active matter systems.
What are Active Matter Systems?
- It is composed of large numbers of self-driven components that extract energy from their surroundings to generate mechanical work. Due to continuous energy input, such systems are driven far from equilibrium and exhibit fascinating collective behaviors like clustering, giant mass fluctuations and anomalous transport.
- Example: The anomalous behavior of active matter systems can be understood by considering a cup of coffee stirred with a spoon. If one stops stirring, the coffee will eventually come to rest due to the internal viscous forces which resist the fluid motion.
- In contrast, imagine stirring a bacterial solution which under suitable conditions (bacterial concentration), can exhibit perpetual or unceasing collective directed motion. This is called Active matter. In cases like this, the viscosity would vanish.
- Significance: This understanding can be useful in nanotechnology applications like building small-scale energy-efficient bio-devices as well as biomedical applications like characterising infection spread in organs, antibiotic resistance and so on.