In the last decade new data has transformed Cosmology into a mature, empirically grounded physical science. The next decade will see vast increases in astronomical data and qualitatively new observationally regimes, including that opened up by gravitational wave astronomy, with the potential of opening a window into the earliest times in the Universe.

Now is also a particularly exciting time for particle physics. The LHC will help determine what models of fundamental physics are valid beyond the scales probed by existing experiments. Candidate theories of physics beyond the standard model generically predict new physics in collider experiments with important ramifications for cosmology.

Thus, upcoming experiments in both cosmology and particle physics will provide new data on dark matter, dark energy and the physics of the early Universe. How these fit into a coherent description at the level of fundamental physics is an open and compelling question: the breakthrough answers will come from theorists closely interacting with groups of talented experimentalists in both fields, and interpreting and building on their findings with new models and creative ideas. Precisely such a confluence of talented faculty now exists at Penn. Penn theorists have been at the forefront of developing new theoretical idea to address cosmological problems, and Penn experimentalists are playing leadership roles in a suite of new experiments that are in the construction, research and development, or planning stages.

Particle cosmology is an interdisciplinary effort between fields with different cultures, funding sources, conferences, and languages. The Center for Particle Cosmology facilitates unfettered interactions and collaborations between these traditionally separate groups, thus creating a new entity with day-to-day interdisciplinary activity. Our mission is the connection of cosmology with new ideas in fundamental physics, directly testable both through the current flux of data from observational cosmology and imminent new particle physics experiments.