what unites fish, birds and magnetic particles

In 2024, particles have become a major topic in both popular culture and academia. Video games and movies are increasingly striving for realism using complex particle symbols. In science, supercomputers make it possible to simulate billions of particles, combine different disciplines and estimate the probability of processes occurring.

New research published in the Journal of Statistical Mechanics: Theory and Experiment, sheds light on the phenomenon of general motion, in which individual objects begin to move as a single unit. Although this phenomenon is well known in particle physics, it also occurs in the macrocosm – for example, in schools of fish. Researchers believe that the ability to move synchronously is explained not only by developed sensory organs, but also by previously unknown physical processes.

Interestingly, the collective movement of fish or birds can be compared in some ways to plasma in fusion reactors. Both phenomena appear similar to liquids such as water or wind. However, the exact mechanisms behind these phenomena are still controversial. Researchers have discovered that fluctuations – changes that disrupt order in a system – play a key role, ultimately leading to organized group behaviour.

Experiments have shown that even magnetic particles respond to fluctuations in an unexpected way, leading to the formation of organized groups. This contradicts previous theories that explained general behavior based on pressure and temperature. Interestingly, similar processes are observed even in complex systems, such as groups of birds guided by visual images.

The researchers created a new model to study collective movement, hoping that their approach will help further study similar phenomena. This model has already shown its effectiveness in the example of active particles experiencing nematic moments – a phenomenon observed in periodic crystals, when atoms line up in rows of co- stretched and synchronized.

Therefore, this study was an important step towards a deeper understanding of the phenomena of general movement in nature.