Recent PhD graduate in Cosmology
Nishant Agarwal is a postdoctoral researcher at the McWilliams Center for Cosmology, Carnegie Mellon University. He received his Ph.D. from the Department of Astronomy at Cornell University in 2011, where he worked with Professor Rachel Bean in the area of theoretical cosmology. He studied and developed models for inflation, a phase of rapid expansion in the early Universe just after the Big Bang, and dark energy, the mysterious form of energy that leads to the current acceleration of the Universe, and how they were constrained by observations.
Nishant’s research studied a variety of models of inflation, such as single scalar field models and brane inflation. “My current research focuses on using an effective field theory for inflation to study the initial conditions of the Universe. I am also using data from the SDSS (Sloan Digital Sky Survey) and WMAP (Wilkinson Microwave Anisotropy Probe) satellite to constrain different models of inflation by looking at signatures of primordial non-Gaussianity in the halo power spectrum and the cosmic microwave background bispectrum”, he explains.
Nishant has also worked on theories of dark energy based on large-scale modifications to gravity, such as scalar-tensor gravity and braneworld scenarios. “I am currently working on massive gravity inspired higher-dimensional models of dark energy”, he added.
During the early years of his Ph.D. at Cornell, Nishant worked as a teaching assistant for undergraduate courses in Astronomy. He was also involved in several outreach opportunities offered by the department, such as Focus for teens, Ask an Astronomer, and career mentoring for undergraduates. “Weekly seminars such as relativity lunch talks were a great forum to discuss research with other faculty members and students”, Nishant says.