Dhayaa's research program focuses on extracting weak lensing data from photometric surveys (like DES, DELVE etc.) and then on using these data to probe the physics of the early Universe, such as that of inflation. He develops simulation-based tools for modeling the lensing signal and thereby constraining such physics. His work shows that with the recent advances in simulation modeling and photometric data quality, the next decade of weak lensing will have a unique role to play in our pursuit of the high-energy frontier in cosmology.
Title: Exploring the frontiers of the primordial universe using weak lensing surveys
Abstract — Widefield galaxy surveys are a powerhouse dataset for studying cosmology and astrophysics. While they were initially designed to study the physics of the late Universe, the data quality can also enable explorations of primordial physics from the earliest epochs. I will first show how measurements of weak gravitational lensing probe the particle physics of inflation in novel ways, providing constraints that are both competitive and complimentary to those from other probes. Achieving these constraints necessitates accurate, simulation-based forward models of structure formation and of the rich astrophysics of gas and stars. I will describe our recent efforts in incorporating the evolution of baryons, by constructing halo-based, data-driven models of such physics and propagating the effects to weak lensing observables. When put together, this framework will enable weak lensing to set competitive constraints on primordial signatures.
