Nonequilibrium Phase Transition

A nonequilibrium phase transition occurs when a system changes its state or behavior because of changing conditions, without reaching a balanced or stable condition beforehand. Unlike traditional phase transitions (like ice melting to water) that happen in equilibrium, these transitions happen in systems constantly in flux—such as traffic flow, chemical reactions, or ecosystems—where energy or matter is continually added or removed. They are characterized by sudden changes in properties, like how traffic suddenly shifts from free-flowing to congested, often leading to new patterns or behaviors emerging in the system.