You’re cruising down the highway when all of a sudden endless rows of brake lights appear ahead. There’s no sign of an accident, no stoplight, no change in speed limit or narrowing of the road. So why is there so much traffic? This frustrating phenomena is called a phantom traffic jam.
Phantom traffic jams form when cars on the road exceed a critical density, generally when cars are spaced less than 35 meters apart. In this dense, but flowing, traffic, minor disturbances can set off a chain reaction. One driver brakes slightly. Each successive driver then brakes a. . .