Credit: Brookhaven National Laboratory
The MUSIC code package helps scientists simulate what happens when two nuclei collide at nearly the speed of light, as illustrated in the above figure. Immediately following the collision, the system is heated to an extremely high temperature, resulting in the creation of a state of matter that behaves as an almost-perfect liquid: the quark-gluon plasma (QGP) that was thought to have filled our universe microseconds after the Big Bang. As the system expands and cools, the nuclear matter evolves from the QGP phase to the hadron (a kind of composite particle composed of quarks and gluons) gas phase and eventually freezes out into particles that fly to detectors, where various properties of the particles are measured. MUSIC's numerical simulations allow scientists to "rewind" these measurements to the early stage of the collisions and study the QGP's transport properties (e.g., viscosity, heat conductivity). Programming MUSIC on GPUs will enable more quantitative comparisons with experimental data from Brookhaven's Relativistic Heavy Ion Collider.