Nuclear Computational Low-Energy Initiative

Atomic nuclei are strongly interacting, quantum many-body systems displaying fascinating properties. They exhibit emergent phenomena characteristic  of large complex systems while at the same time being laboratories of most fundamental laws of nature. The goal of the  Nuclear Computational Low-Energy Initiative (NUCLEI) project is to use advanced applied mathematics, computer science, and physics to accurately describe the atomic nucleus in its entirety.

In this proposal, we will build on previous successes to treat a wide range of nuclei and study their electroweak transitions and reactions important in both terrestrial experiments and astrophysical environments. We will employ advanced quantum many-body methods, ranging from ab initio methods such as the nuclear shell model, coupled cluster, in-medium similarity renormalization group, and quantum Monte Carlo, to the density functional methods used to treat complex nuclei and inhomogeneous nucleonic matter.  We will develop advanced applied mathematics and computer science  to allow the resulting algorithms to perform efficiently on the fastest available computers, optimize the input interactions and operators, and provide reliable uncertainty quantification of the results. The input interactions and currents developed by us will interface with the multinucleon lattice quantum chromodynamics (QCD) results as these become available.  Such a coupling is critical for providing complete understanding of nuclei and their reactions rooted in the theory of strong interactions; in the long term, this will result in unifying the fields of nuclei and hadrons. Our computational studies will impact experimental programs, including existing low-energy nuclear physics facilities, the future Facility for Rare Isotope Beams, Jefferson Laboratory, and neutrino experiments.