Einstein relation

The Einstein relation connects how particles move due to random thermal energy (diffusion) with how they respond to an external force (mobility). It states that the rate at which particles spread out, caused by their thermal motion, is directly related to how easily they can be pushed by a force. Mathematically, it links the diffusion coefficient and mobility through temperature, showing that higher temperature increases both diffusion and the particles' responsiveness to forces. This relation is fundamental in understanding microscopic transport processes in physics and chemistry.