Rutgers University Astrophysics Special Seminar - Added

Upcoming data from instruments such as JWST, large ground-based telescopes, and future 21cm experiments will soon open a new window into the early Universe. These observations will allow us to address a number of exciting questions related to the first billion years after the Big Bang: What were the properties of the first stars and galaxies? How did the first supermassive black holes form? How and when did reionization of neutral hydrogen in the intergalactic medium occur? In this talk, I will discuss some of the theoretical work required to interpret future observations and answer these questions. I will begin by describing models of the large-scale distribution and abundance of the first metal-free stars and how these models can be utilized to make predictions for a range of different observables. I will then describe how the existence of billion solar mass supermassive black holes only a billion years after the Big Bang presents an interesting puzzle and discuss one possible solution, the formation of massive (~100,000 solar mass) black hole seeds formed through direct collapse of gas in pristine dark matter halos. I will conclude by discussing galaxy intensity mapping, a promising new observational technique to study cosmology, galaxy evolution, and reionization by measuring large-scale spatial fluctuations in galaxy line emission.