Brownian motor ramifications of the Fluctuation Theorems, Pumping Quantization Theorems, and Pumping-Restriction Theorems. Brownian motor Brownian motors are nano-scale or molecular devices by which thermally activated processes (chemical reactions) are controlled and used to generate directed motion in space and to do mechanical or electrical work. These tiny engines operate in an environment where viscosity dominates inertia, and where thermal noise makes moving in a specific direction as difficult as walking in a hurricane: the forces impelling these motors in the desired direction are minuscule in comparison with the random forces exerted by the environment. Because this type of motor is so
Brownian motion consideration the velocity of the Brownian particle, "U", which depends on the collisions that tend to accelerate and decelerate it. The larger "U" is, the greater will be the collisions that will retard it so that the velocity of a Brownian particle can never increase without limit. Could such a process occur, it would be tantamount to a perpetual motion of the second type. And since equipartition of energy applies, the kinetic energy of the Brownian particle, formula_30, will be equal, on the average, to the kinetic energy of the surrounding fluid particle, formula_31. In 1906 Smoluchowski published a one-dimensional