Predicting Traffic Jams

   Science and math can do a lot of things. They can predict severe thunderstorms. They can predict the likelihood of an asteroid striking the earth (not very, thank God). They can even predict who might be candidates for Altzheimers or other diseases.

   Yet one phenomenon they have yet to conquer. Or have they?

   I am writing about traffic jams. Most of us have found ourselves in stock-still traffic, and we frantically scan the radio for some sort of explanation. Moments later, it clears up, and further travel shows nothing to be amiss; no emergency vehicles or tow trucks on the side of the road.

   Wired Magazine has an article which decribes the effort of MIT scientists to minimize the number of  these "phantom jams." As the article explains:

Phantom jams are born of a lot of cars using the road. No surprise there. But when traffic gets too heavy, it takes the smallest disturbance in the flow – a driver laying on the brakes, someone tailgating too closely or some moron picking pickles off his burger – to ripple through traffic and create a self-sustaining traffic jam.
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The mathematics of such traffic jams are strikingly similar to the equations that describe detonation waves produced by explosions, said Aslan Kasimov, a lecturer in MIT’s Department of Mathematics. Realizing this allowed the reseachers to solve traffic jam equations that were first theorized in the 1950s. The MIT researchers even came up with a name for this kind of gridlock – “jamiton.” It’s a riff on “soliton,” a term used in math and physics to desribe a self-sustaining wave that maintains its shape while moving.

   Yes, it's a little egghead-y, but still interesting since it is an experience many of us share. Here's a video which shows how jams happen.



   For more on this topic, read the article here.