1. Is your daily slog through a non-equilibrium system of interacting particles — how physicists define vehicular traffic — getting you down? Us too, especially when it slows for no apparent reason.
2. According to a study in the New Journal of Physics, traffic jams develop spontaneously when vehicle density exceeds a critical level, beyond which minor fluctuations in the flow of individual vehicles destabilize the whole thing.
3. In fact, even construction or an accident isn’t directly responsible for congestion; the cause is the increase in vehicle density.