'Collide the Ions' walkers dressed in blue and yellow T-shirts walked around Brookhaven Lab's Relativistic Heavy Ion Collider ring road in opposite directions. Halfway around the ring, the walkers symbolically "collided." More Information
When heavy ions collide at high energies at Brookhaven's Relativistic Heavy Ion Collider, the components of the nuclei melt to form a hot soup of their constituent particles. A new model that describes the patterns of particles flowing out from this "quark-gluon plasma" suggests that the resistance to flow is close to the ideal limit used to define a "perfect" fluid.