My research currently focuses on deriving nuclear physics from the underlying theory of quantum chromodynamics (QCD). This relies both on numerical lattice QCD calculations of nuclear properties using high-performance computing, and the application of effective field theory methods both at the hadronic level and at the level of the nuclear structure. Recently, I have also been interested in (i) a way of thinking about QCD which is called light-front or null-plane QCD, which I believe provides novel insights regarding hadronic structure, and (ii) aspects of atomic physics at the interface of two and three spatial dimensions.

I work on applications of time-dependent density-functional theory to laser and other electromagnetic interactions with condensed matter. Specific topics include dielectric response, dichroism, high-field response, and coherent phonon generation

Quantum many-body nuclear physics and related systems.My research is lately focused on the structure, phase transitions and dynamic properties of strongly interacting systems of many fermions, typically nucleons and cold atoms. I employ a wide spectrum of many-body techniques, among them: quantum Monte Carlo for evaluation path integrals, density functional theory, high performance computing on leadership class computers.

I work on applications of quantum field theory to various aspects of nuclear and particle physics, including lattice field theory for QCD and supersymmetry, effective field theory for low energy nuclear physics, physics beyond the standard model, and particle cosmology.

I work on all aspects of theoretical nuclear physics, including its overlaps with particle phenomenology and atomic physics. Current interests include proton structure, effects of quantum chromodynamics in nuclei, effective field theory approaches to nuclei, studies of fundamental symmetries in nuclei, and nuclear reaction theory at low energies.

I am interested in nuclear and neutrino processes that underly extreme astrophysical phenomena (neutron star structure and evolution, core-collapse supernova, x-ray bursts, magnetar flares, and gamma-ray bursts). Other interests include the application of quantum many-body theory to nuclei, cold atom gases, nuclear matter, dense quark matter, and related phases in neutron stars.

My scientific research is focused on using the numerical technique called Lattice QCD to reliably calculate the properties and interactions of nuclei. Presently such calculations are not possible, but within the next few years, with the deployment of increasing computational resources, this will become possible. As a member of the NPLQCD collaboration, we are developing the technology and codes required to perform such calculations. Ultimately, these calculations will provide a rigorous underpinning for Nuclear Physics, and will allow for the quantification of uncertainties in calculations of low-energy nuclear processes. Important steps continue to be made toward this goal.