Quantifying the phase structure of matter at extreme temperature and density has profound impacts on understanding how quarks and gluons, the building blocks of nucleons, interact collectively and elucidating the property of the early Universe within the first microsecond after its creation in the Big Bang. High energy collisions of atomic nuclei create the Quark-Gluon Plasma (QGP), a new state of matter at about 2 trillion degrees Kelvin. The QGP behaves like a nearly perfect fluid, which flows ten times better than water. This project will develop a new theoretical framework to model how small ripples evolve in the QGP fluid. By decoding these ripples' traces in the experimental measurements, the PI will quantify the QGP properties and identify whether the nature of phase transition from ordinary matter to the QGP is like water transits to vapor. This project interweaves nuclear physics, high-performance computing, and advanced machine learning techniques. The interdisciplinary nature of the project helps the participating students acquire solid training in theoretical physics as well as computational science skills.
This project will develop the first theoretical framework to model the 3D dynamical evolution of stochastic fluctuations in relativistic heavy-ion collisions. By studying how fluctuations of energy, momentum, and charge density dissipate in the collision system, one can quantify the thermal, critical, and transport properties of the QGP using experimental measurements. By integrating the proposed framework with the Bayesian analysis and applying them to heavy-ion collisions over wide ranges of collision energies, the PI and his group will extract quantitative phenomenological constraints on the QGP properties. Searching the critical point signature in experimental data is slated to break new ground in the application of deep learning techniques to physical science. This proposed framework serves as an essential infrastructure to guide and interpret the experiments at Relativistic Heavy Ion Collider Beam Energy Scan phase II, and high luminosity runs at the Large Hadron Collider. The theoretical advancement in understanding the dynamics of such a strongly-coupled many-body system can generate interesting cross-talk with cold atomic physics, cosmology, and neutron star/black mergers.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
