My research lies at the interface of nuclear and high energy physics with cosmology. My work focuses on several questions:
1. Why is there more matter than antimatter in the present universe and what is the nature of non-baryonic dark matter? Generation of the matter-antimatter asymmetry of the universe
requires physics beyond the Standard Model (BSM), and this physics may be linked to the physics of dark matter as well. I study both the theoretical methods for computing the matter-antimatter
asymmetry and apply them various scenarios for BSM physics. The methods include quantum field theory in finite temperature and out-of-equilibrium environments. I have worked extensively on supersymmetric electroweak baryogenesis and am now investigating non-supersymmetric scenarios as well.
This research also emphasizes possible experimental tests, such as searches for permanent electric dipole moments and LHC searches for new scalar particles.
2. What additional forces were present in the early universe? Several theoretical considerations and experimental observations point to the existence of BSM physics that would be associated with new interactions that were relatively more pronounced in the early universe than they are today. I have been exploring the implications of scenarios such as supersymmetry and extensions of the Standard Model Higgs sector for highly sensitive experiments being carried out at low-energies as well as for new particle searches at the LHC. I am particularly interested in what complementary information experiments at these two “frontiers” may yield regarding BSM interactions.
3. How does QCD make nucleons? Quantum Chromodynamics is often said to be the simplest fundamental theory to write down and the most difficult to solve. Explaining how it gives rise to the internal structure of nucleons and other hadrons as well as to their interactions remains a forefront problem in nuclear physics. I study questions in this area using a combination of effective field theory methods, perturbative QCD, and models. I am also interested in how electroweak precision measurements, such as parity-violation in electron scattering, can provide novel information about the quark and gluon dynamics of hadrons.