09/20/2022
By Joanne Gagnon-Ketchen
Abstract: Prof. Nishant Agarwal will start with a brief overview of research in the Theoretical Cosmology Group at UMass Lowell, whose broad goal is to understand the origin, composition, and evolution of the Universe using methods in theoretical cosmology, quantum field theory, and general relativity. He will focus on two specific directions. The goal of the first direction is to develop a formulation of quantum field theory that includes initial state and dissipative effects. He will discuss the construction of out-of-equilibrium Green’s functions in the presence of Gaussian initial states and linear dissipation and discuss implications for the quantum-to-classical transition of perturbations in the early Universe. He will also talk about related work on loop corrections to correlation functions and entanglement in quantum field theory. The goal of the second direction is to use the large-scale galaxy distribution for probing key cosmological parameters. He will discuss results on using higher-order galaxy statistics to significantly improve constraints on, for example, the growth rate of matter perturbations, and discuss implications for the theory of gravity on large scales. He will also talk about related work on the growth rate in other theories of gravity and nonlinearities in the spectrum of primordial perturbations.
Bio: Nishant Agarwal is an Assistant Professor at UMass Lowell, where he leads the Theoretical Cosmology Group. He obtained his undergraduate degree in physics from the University of Delhi (India) and his master’s degree in physics from the Indian Institute of Technology Kanpur (India). He then joined the Department of Astronomy and Space Sciences at Cornell University, where he completed his Ph.D. in theoretical cosmology. Based on his Ph.D. work, Nishant was awarded a McWilliams postdoctoral fellowship at Carnegie Mellon University, where he pursued research in high energy physics, and in theoretical cosmology with the Sloan Digital Sky Survey team. He next moved to the Pennsylvania State University as an Institute for Gravitation and the Cosmos postdoctoral fellow, where he continued his research in theoretical cosmology and high energy physics. He joined UMass Lowell as an assistant professor in 2016.