## Cosmology and Gravity Theory

**CONTACT:**

Angela Q. Lewis

208 Jadwin Hall

**609-258-0720**

Working closely with the experimental group, we use astrophysical, particle physics and *string* theory combined with observations to study gravitation and the origin and evolution of our universe.

In cosmology and astrophysics, Einstein's General Theory of Relativity

(GR) is the foundation for everything from models of the universe to the collision of black holes. Our group is a pioneer in the use of numerical GR to understand such things as the gravitational wave signature of merging black hole and neutron star systems, the properties of spacetime and matter fields approaching the big bang , and elements of string theory.

The study of the nature of large-scale structure was pioneered in this group *three* decades ago, and we continue to make leading contributions to theories of the origin of this structure. Crucial elements in the work include the measurements by the experimental group of the *2.725* K thermal background radiation, deep observations of galaxies, and the Sloan Digital Sky Survey that operates out of the *neighboring* Department of Astrophysical Sciences.

The origin of the physical universe and the cosmological model that describes its evolution must ultimately be explained by fundamental physics. Our group also studies the relationship between particle or

string* physics and theories of the very early universe, dark matter, the cosmological constant and quintessence. These studies have profound implications for both fundamental physics and cosmology.

#### Faculty

- Joanna Dunkley:Cosmic microwave background, large scale structure, cosmology, statistical analyses
- Frans Pretorius: Einstein's theory of general relativity, specializing in numerical solution of the field equations
- Paul J. Steinhardt: Inflationary cosmology; dark matter and dark energy; string cosmology; quasicrystals
- Jim Peebles: Theories for large scale structure formation, cosmological tests (Emeritus)

#### Postdoctoral Research Scholars

- Lasha Berezhiani
- Anna Ijjas
- Vasileios Paschalidis
- Kent Yagi