Subdiffusion refers to a type of diffusion process that occurs in physical systems where the rate of particle movement is slower than the standard Brownian motion. In subdiffusion, particles either exhibit reduced mobility or have limited access to free space, leading to a slower and more restricted movement pattern compared to normal diffusion.
The term "subdiffusion" is widely used in various scientific disciplines, such as physics, chemistry, and biology, to describe the behavior of particles or molecules in complex environments. It often arises in systems with obstacles, bottlenecks, confinement, or heterogeneous media, where the motion of particles is hindered or obstructed.
The mathematical description of subdiffusion typically involves the use of stochastic processes, such as fractional Brownian motion, fractional Langevin equation, or random walk models with heavy-tailed distributions. These models account for the long-range correlations and anomalous dynamics observed in subdiffusion.
The study of subdiffusion has important implications in a range of fields. For instance, it is relevant in understanding the transport of molecules in living cells, the spread of pollutants in porous media, the behavior of complex fluids, and the diffusion of financial data in economics. Analyzing the characteristics and mechanisms of subdiffusion can provide insights into the underlying structure and dynamics of the systems under investigation.
