We think #traffic jams need a trigger: #accident, #roadworks, lane closure The most frustrating queues have no obvious cause at all. These are known as phantom traffic jams Researchers asked 22 drivers to drive circular track & maintain constant speed & safe distance from vehicle in front In minutes tiny, unavoidable braking differences grew into stop-start wave that travelled continuously around the circuit; Yet there being no obstacle anywhere https://theconversation.com/dont-change-lanes-the-maths-of-holiday-traffic-jams-287389?utm_medium=mastodon_fediverse #motorways #freeways