Title: Insights from galaxies at long distances

Speaker: Pierre Zhang (ETH Zurich)

Time: 3:30 pm, Jan 12 (Friday) 2024

Location: 理科楼C109

Abstract: Driven by an EFT approach to gravitational clustering, I will show how one can extract cosmological information from the Large-Scale Structure beyond the linear regime. After reviewing the predictions for galaxies at long distances, I will present interfaces with observation. As revealed by recent analyses of galaxy data, this line of action can push down limits on ΛCDM, and extensions.

Bio: After obtaining a Master in Particle Physics and Cosmology at the Grenoble-Alpes University, France, in 2017, I obtained a PhD in astrophysics at the University of Science and Technology of China in 2022. Since then, I am holding a postdoctoral position at ETH Zurich. My research focuses in exploring the Large-Scale Structure of the Universe from the bottom-up: at sufficiently long distances, localized objects such as galaxies can be described as a sort of fluid which properties are derived from symmetry principles. By clarifying what this means, we can learn how to read in theoretically-controlled way the cosmic maps, such as the ones drawn by galaxy surveys. As a matter of fact, the increasing data volume of galaxy maps is about to become our main cosmological probe. My research aims to provide theoretical keys and practical tools to access the information encoded in those maps, such as hints on the Universe’s first instants, properties of the neutrinos, or the nature of gravity.