Topics in Particle Theory

College Of William And Mary, Williamsburg VA

Investigators

Abstract

This award funds the research activities of Professors Christopher Carone, Joshua Erlich, and Marc Sher at the College of William and Mary. The Standard Model of particle physics was developed 35 years ago, and has survived numerous experimental tests. Nonetheless, many aspects of the Standard Model remain mysterious: What is the origin of the masses of the known elementary particles? What accounts for the hierarchical structure of their mass spectrum? Why is the gravitational force so much weaker than the electromagnetic, weak and strong nuclear forces? What is the mysterious dark matter that seems to be pervasive in our universe? Professors Carone, Erlich, and Sher aim to address these and related questions by considering possible physics beyond the Standard Model, including new particles (for example, their proposed work on extended Higgs sectors), new symmetries (for example, their proposed work on models of neutrino masses), and new structures of space-time (for example, their proposed work on higher-dimensional models and holography). It is exciting that much of the work proposed by these principal investigators might be tested at the Large Hadron Collider (LHC). The LHC, which is the highest energy proton-proton collider in the world, has begun full operations. Data from the LHC is imminent and is likely to lead to nothing less than a new Standard Model for the next generation of particle physicists, i.e., a new theoretical picture of the fundamental building blocks of matter and their interactions. In addition, the PIs have proposed work on dark matter, mysterious particles that will be studied not only at the LHC, but also at numerous direct detection experiments around the world. The PIs will consider possible models of a "dark sector", which may involve fairly light particles with very weak couplings to matter. To study such a sector experimentally, one requires high-intensity particle beams at low energies, and the PIs will consider how these models may be explored using the high-luminosity electron beam at Jefferson Lab. This effort may lead to new connections between the nuclear and high-energy physics communities. This project is also envisioned to have significant broader impacts. Professors Carone, Erlich, and Sher will involve graduate students and a postdoc in their research, providing critical training to junior physicists who are beginning research in this field. The postdoc will be jointly funded with Jefferson Lab, and will facilitate a synergy between two different disciplines in physics. The PIs also intend to give public lectures on their research results and involve undergraduate students in their work.