The model serves to understand the phenomenon of propagation of matter in a medium under the influence of Brownian motion.

If there are reasons in space for random movement of objects (temperature, vibration, etc.), then the distribution of objects will obey the law of diffusion, which can be expressed in a simple form as follows. The rate of the observed change in the concentration of objects in two adjacent regions is proportional to the concentration difference (gradient) with a certain coefficient, which is called the "diffusion coefficient".

Click on the map to position the substrate source and see how it will dissipate. Change the diffusion coefficient using the slider.