Entropy harvesting

The paper introduces the notion of "entropy harvesting" in physical and biological systems. Various physical and natural systems demonstrate the ability to decrease entropy under external stimuli. These systems, including stretched synthetic polymers, muscles, osmotic membranes and suspensions containing small hydrophobic particles, are called "entropic harvesters". Entropic force acting in these systems increases with temperature. Harvested entropy may be released as mechanical work. The efficiency of entropy harvesting increases when the temperature is decreased. Natural and artificial energy harvesters are presented. Gravity as an entropic effect is discussed.