In gases, this process's coefficient is equal to one-third times mean free path times mean thermal speed, and a law driven by this process sets a property's time derivative linearly proportional to its second spatial derivative.
Adding terms governing this process due to the Bloch equation gives the Bloch-Torrey equation. An "apparent" coefficient governing this process is measured in a method in which each voxel is assigned a rate and direction; that method is used in tractography. In gases, this process's coefficient is equal to one-third times mean free path times mean thermal speed, and a law driven by this process sets a property's time derivative linearly proportional to its second spatial derivative. The (*) Einstein-Smoluchowski relation finds this process's namesake constant proportional to mobility, Boltzmann's constant, and temperature. The flux due to this process is proportional to the concentration gradient, as stated in Fick's Laws. For 10 points, name this process where particles move from areas of high to low concentration.
Adding terms governing this process due to the Bloch equation gives the Bloch-Torrey equation.
diffusion