Theoretical physicists at Brookhaven National Laboratory and their collaborators have just released the most precise prediction of how subatomic particles called muons—heavy cousins of electrons—“wobble” off their path in a powerful magnetic field. To tackle the challenge, the physicists used a method known as Lattice QCD, originally developed at Brookhaven Lab, and powerful supercomputers. The largest was the Leadership Computing Facility at Argonne National Laboratory, while smaller supercomputers hosted by Brookhaven’s Computational Sciences Initiative (CSI) were also essential to the final result.