Self propulsion breaks equilibrium by locally generating forces, driving the swimmer. Important is that the drive is coupled to the particle, and not an external field.
Young Investigators Group Dr. Jens Elgeti
"Life is not in equilibrium" - this simple statement shows a gap in our physical understanding of the world. Living matter such as motile bacterial colonies, developing embryos or growing plants, does not fulfill the criterion of equilibrium as it is out of equilibrium. Particularly for living matter, this drive out of equilibrium stems from the material itself: Cells move and pull, they grow and divide, leading to novel "living" terms in the classical description.
While living matter takes many forms, our group focuses on two particular forms of activity: Microswimmers, where molecular processes generate forces driving the swimmer, and growth, where matter is not conserved, but generated by the material itself.