Perpetual Motion with Maxwell’s Demon

A method for producing a temperature gradient by Brownian motion in an equilibrated isolated system composed of two fluid compartments and a separating adiabatic membrane is discussed. This method requires globular protein molecules, partially embedded in the membrane, to alternate between two conformations which lie on opposite sides of the membrane. The greater part of each conformer is bathed by one of the fluids and rotates in Brownian motion around its axis, perpendicular to the membrane. Rotational energy is transferred through the membrane during conformational changes. Angular momentum is conserved during the transitions. The energy flow becomes asymmetrical when the conformational changes of the protein are sterically hindered by two of its side‐chains, the positions of which are affected by the angular velocity of the rotor. The heat flow increases the temperature gradient in contravention of the Second Law. A second hypothetical model which illustrates solute transfer at variance with the Secon...