Spring 2023 Physics Colloquium: Unravelling the physics of the early universe with upcoming CMB and galaxy observations

Abstract: Diverse observations have established the standard cosmological model, known as $\Lambda CDM$. Within this model, the Universe began in a hot dense state filled with tiny primordial density fluctuations. These fluctuations grew as they collapsed under gravity and eventually became the seeds of the galaxies throughout the Universe. A key question is where did these initial perturbations come from? The leading model for their creation, known as inflation, posits that these arose from quantum vacuum fluctuations that were stretched to cosmic scales by a period of exponential expansion of the Universe. Many models predict that this process will leave a distinct statistical signature on the primordial density perturbations. In this talk I will discuss how we can use the statistical properties of relic radiation from the hot initial state, known as the cosmic microwave background (CMB), and the spatial distribution of galaxies to search for this primordial signature. In particular, I will highlight some of the opportunities and challenges facing future experimental searches.

In-Person only. Refreshments in PAS 218 at 2:45PM