Grant: Subatomic Physics Envelope - Individual

This research program uses computer calculations to study the physics of elementary particles. The method is called lattice gauge theory and it has become a standard tool for learning about quarks and gluons, which are the building blocks of protons, neutrons, and all other hadrons. My research group is using lattice gauge theory to advance knowledge in three specific directions. 1. In recent years, several experiments have discovered dozens of exotic hadrons, sometimes called tetraquarks, that each contain a pair of heavy quarks surrounded by lighter quarks and gluons. Several theoretical proposals have been put forward to describe the properties of these tetraquarks, but a complete understanding will require creative new applications of lattice gauge theory. Our group is using lattice gauge theory to study this category of exotic hadrons. 2. Astrophysical observations indicate the existence of dark matter, but the standard model of particle physics contains no dark matter particle. We are using lattice gauge theory to study a minimal model of dark quarks and dark gluons. Output from the lattice gauge theory computations can be combined with astrophysical observations to learn whether this minimal model could provide a viable description of dark matter. 3. Although lattice gauge theory has become indispensable for modern subatomic physics, there are still many important scenarios that cannot be handled by the standard lattice approach. Examples include particle collisions as a function of time, and nuclear matter at high densities (such as in neutron stars or the early universe). Use of the Hamiltonian formalism on quantum computers could make these scenarios accessible to lattice methods. We are exploring this possibility by testing various implementations of lattice gauge theory on quantum computers that are available today.