# Gravity, Cosmology, High Energy Physics, String Theory

The fundamental theory group within the Department encompasses the traditional areas of relativistic field theory that include gravitational physics, physical cosmology, particle physics and high-energy theory, and string theory. This group also has ties to other theorists in the Department, including those in non-relativistic quantum many-body theory, nuclear theory, and astrophysics. The fundamental theory program is also one of the three pillars (along with astrophysics and nuclear physics) of the Department’s participation in the multi-university CoSMS Institute.

Current research within the group includes study of sources of gravitational radiation and radiation reaction in general relativity, applications of numerical relativity, calculations in relativistic astrophysics of massive black holes, beyond standard model of particle physics (including dark matter), quantum gravity phenomenology, and foundations of quantum mechanics.

The theory group hosts a number of distinguished visitors each year. Recently these have included Patrick Brady (Univ. Wisc-Milwaukee), Mark Hannam (Cardiff University), and Niels Warburton (MIT).

String theorists within the group have a very active weekly UNC-Duke seminar program. This group seeks to answer questions such as ‘How can quantum mechanics and gravity be combined in a single theoretical framework?,’ ‘What is the nature of space and time at the Planck scale?,’ and ‘Why is the scale of electroweak symmetry breaking so much lower than the Planck scale?’ The group’s work addresses these questions through the study of string theory, the only known consistent theory of quantum gravity. This includes the study of strings at strong coupling via M-theory and F-theory, as well as the resulting low energy effective field theories generated by compactifying the extra dimensions predicted by superstring theory. Additional research threads include the study of physics beyond the Standard Model of particle physics, especially those extensions motivated by strings; the mathematical and formal structure of scattering amplitudes; and the study of superconformal field theories, especially those in more than four spacetime dimensions.

The group at present has over ten graduate students, many of whom are supported by major research grants from the National Science Foundation. Our graduates have pursued highly successful careers in academia, industry, finance, and national laboratories.

## Faculty and Research Specialties

**COSMOLOGY**

Jack Ng, Adrienne Erickcek, Chuck Evans, Laura Mersini-Houghton

**HIGH ENERGY / PARTICLE PHYSICS**

Jack Ng, Louise Dolan

**QUANTUM GRAVITY**

Jack Ng, Chuck Evans, Louise Dolan

**STRING THEORY**

Louise Dolan