Locked behind heavy blue security doors in the heart of America's most sensitive weapons lab, Blue Mountain is the pinnacle of computing, actually 6,200 processors in 550 blue and gray computer cabinets, each rising six feet high and arrayed in 14 rows like a bountiful metallic cornfield. It is a supercomputer so fast it can process in one second the entire contents of the Library of Congress, albeit it a simple task compared to simulating rush hour. Understanding the timing and dynamics of phase changes in traffic, like those in nature, poses a challenge for physicists. But this could hold the key to easing the frustration of commuters, including those traveling along the Outer Loop of the Capital Beltway near the Persimmon Tree Road overpass in Montgomery County on a typical Tuesday morning. When traffic is light, motorists drive much as they like, moving at the speed they want and changing lanes easily.
Motorists are comparable to steam particles with great freedom of movement.
As the road becomes crowded, motorists suddenly lose much of their freedom and are forced to drive as part of the overall traffic stream, moving at the speed of the general flow and often unable to change lanes. Like water freezing into ice, the motorists are stuck in place.