The weird, counter-intuitive science of traffic jams

— Self-driving cars steered by robots could do a lot to reduce traffic jams. That’s because the human inability to maintain a steady, constant speed on the road is responsible for a lot of congestion. Japanese physicists discovered this when they had people try to drive around in steady speeds on a circular road. Jams materialized out of nowhere. People braked erratically and started responding uncertainly to people ahead of them.