Collective Motion of Self-Propelled Particles: Kinetic Phase Transition in One Dimension

We demonstrate that a system of self-propelled particles exhibits spontaneous symmetry breaking and self-organization in one dimension, in contrast with previous analytical predictions. To explain this surprising result we derive a new continuum theory that can account for the development of the symmetry broken state and belongs to the same universality class as the discrete self-propelled particle model. [S0031-9007(98)07911-3]