Randomness, Brownian motion, and Mathematics! Well, don’t take it they aren’t connected. Dive in now to check out what prompts this article here.
Well, there’s this word called Brownian motion. Let me give a brief explanation: Brownian motion defines the random movement of particles in fluids, however, as the definition explains, this revolutionary model only functions when a fluid is static, or at equilibrium.
Fluids contain tiny swimming microorganisms that move by themselves. This is the process in the real world. These self-propelled swimmers can lead to movement or stirring in the fluid. Thus these cause the fluid to move away from its equilibrium.
It is revealed through experiments that non-moving ‘passive’ particles can exhibit unusual, loopy motions when interacting with ‘active’ fluids containing swimmers. Such movements don’t fit with the conventional particle behaviors described by Brownian motion, and so far, scientists have worked hard to resolve how such large-scale chaotic movements arise from microscopic interactions between individual particles.
They have dealt with this issue. Researchers from the Queen Mary University of London, Tsukuba University, École Polytechnique Fédérale de Lausanne and Imperial College London bring the result. They have brought forward their argument to describe observed particle movements in these dynamic environments.
They also prescribe that this alternative design can support us make forecasts about real-life behaviors in biological systems, like the foraging methods of swimming algae or bacteria.
“Brownian motion is widely used to describe diffusion throughout physical, chemical and biological sciences; however it cannot be employed to define the diffusion of particles in additional active systems that we usually observe in actual life,” said Dr. Adrian Baule, Senior Lecturer in applied mathematics at the Queen Mary University of London, who took care of the project.
Researchers could develop a valuable model for particle motion in ‘active’ fluids, which accounts for all experimental observations. Their extensive calculation reveals that the effective particle dynamics follow a so-called ‘Lévy flight’, which is extensively accepted to illustrate ‘extreme’ movements in complex systems that are very far from typical behaviour, like in ecological systems or earthquake dynamics.
Dr. Kiyoshi Kanazawa from the University of Tsukuba, and the first author of the study, said that till now there was no evidence of how Lévy flights can indeed occur based on microscopic interactions that obey physical laws.
Kanazawa told that their results show how Lévy flights can arise because of the hydrodynamic interactions between the active swimmers and the passive particle, which was surprising.
The team discovered that the density of active swimmers also affected the duration of the Lévy flight regime, suggesting that swimming microorganisms could exploit the Lévy flights of nutrients to decide the best foraging strategies for various environments.
The first picture of Brownian motion was in 1827 when he noticed the random movements demonstrated by pollen grains when combined with water by English botanist Robert Brown.
Decades later the eminent physicist Albert Einstein advanced the mathematical model to clarify this behavior, and in doing so showed the existence of atoms, establishing the foundations for widespread applications in science and beyond.
The research was published in Nature Journal