The Relativistic Heavy-Ion Collider (RHIC) at BNL has played a central role in establishing the quark–gluon plasma (QGP) as a strongly coupled form of QCD matter that behaves collectively as a near-perfect liquid. Its major achievements have transformed the field of nuclear physics and raised profound new questions in the study of QCD. These include how rapid thermalization can occur, what is the microscopic mechanism of a strongly coupled QCD fluid, and the nature of the QCD phase transition.

The Large Hadron Collider (LHC) extends heavy-ion studies into a higher-energy regime characterized