Answers For Traffic Congestion

"Viewed merely as a physical flow, a traffic jam seems as simple as water moving more slowly through a constriction—a problem that appears easy to fix. But even adding a lane to a highway, for reasons no one quite understands, sometimes creates new tie-ups. For decades, the behavior of heavy traffic has stymied a think tank's worth of highway engineers, city planners, fluid dynamicists and social scientists."

Thanks to Chris Steins