Colliders in the Sky: Probing Fundamental Physics with Cosmological Data

Abstract: The first fractions of a second after the Big Bang likely involved physics operating at energy scales orders of magnitude above those accessible to terrestrial experiments. This epoch — known as inflation — played a crucial role in cosmic history, sourcing quantum fluctuations that seed structure formation in the late Universe. Despite its importance, the inflationary period is poorly understood, and little is known about its particle content or interactions. In this talk, I will describe how modern cosmological observations allow us to probe this ultra-high-energy regime by searching for subtle patterns in the distribution of cosmic microwave background radiation and galaxy positions. I will present recent results using observational data, highlighting how new techniques enable precision measurements of primordial particle physics, effectively turning the Universe into a “cosmic collider”. I will conclude by discussing how the next generation of survey data, if modeled precisely enough, could lead to significant advancements in our knowledge of the inflationary Universe.