Collective phenomena and states in traffic and self-driven many-particle systems

Classical many-particle systems show a variety of interesting new phenomena when self-driving and dissipative forces (and fluctuations) are added. Although these phenomena are often very different from the ones known from equilibrium thermodynamics, their description is mostly possible by applying and extending methods from statistical physics and nonlinear dynamics. Some of the questions now understood are the following: Why are vehicles sometimes stopped by so-called “phantom traffic jams”, although they all like to drive fast? What are the mechanisms behind stop-and-go traffic? Why are there several different kinds of congestion, and how are they related? Why do most traffic jams occur considerably before the road capacity is reached? Can a temporary reduction of the traffic volume cause a lasting traffic jam? Why do pedestrians moving in opposite directions normally organize in lanes, while nervous crowds are “freezing by heating”? Why do panicking pedestrians produce dangerous deadlocks? What consequences does their herding behavior have?