At CERN's Large Hadron Collider (LHC), studies of rare processes allow scientists to infer the presence of heavy particles, including undiscovered particles, that cannot be directly produced. Such particles are widely anticipated to exist beyond the Standard Model, and could help explain some of the enigmas of the universe, such as the existence of dark matter, the masses of neutrinos (elusive particles originally thought to be massless) and the universe's matter-antimatter asymmetry.