The PI proposes research at the interface of high energy theory, astrophysics, and cosmology. Recent measurements of the cosmic microwave background (CMB) have corroborated the basic picture of inflationary cosmology, which gives an approximate prediction of a spatially flat universe with scale invariant density perturbations on the largest length scales. If the inflationary paradigm is correct, the CMB provides a handle onto the earliest history of the universe. The PI plans to investigate the nonadiabatic interplay between curvature and isocurvature perturbations arising from particle production during inflation, derive signatures of superheavy dark matter (and other nonthermal scenarios), and search for novel consistency conditions for inflationary scenarios. These investigations will not only provide new ways to interpret existing and future CMB and structure formation data, they will allow constraints on conjectures of physics beyond the Standard Model. Another set of proposed research activities focus on understanding the cosmological implications of the anticipated discovery of Higgs and other new TeV scale physics at the LHC. In this context, one important handle for cosmology is the potential generation of the baryon asymmetry at the electroweak phase transition. Because electroweak baryogenesis is a complicated phenomenon, a prediction of the baryon asymmetry accurate to an order of magnitude still requires refinements. The final set of proposed research actvities are centered on the idea of alternate theories of gravity, which have a multitude of implications for cosmology. One avenue for further exploration is in the context of extra dimensions, and the other is in the context of modifications of fourdimensional Einstein-Hilbert action (particularly in the infrared). The PI plans to explore quantum as well as classical field theoretic aspects of the fields coupled to the alternate gravity.
