Joint cosmology seminar at MIT:

Tuesday, November 21, 2023, 2:30 pm

Cosman Seminar Room\\

Center for Theoretical Physics\\

Building 6C, Room 6C-442\\

Massachusetts Institute of Technology

**The Large-Scale Structure Renormalization Group: Bridging the Gap Between QFT and Cosmology**

Henrique Rubira

Technical University of Munich

Abstract:

Major improvements in the theoretical aspects of Cosmology have been possible in recent years due to QFT-inspired methods, such as the effective field theory of large-scale structure (EFTofLSS). In this talk, I will explore further connections between high-energy physics and cosmology. I will present a systematic approach to renormalizing the galaxy bias parameters using path integrals and a finite cutoff scale $\Lambda$. I will derive the differential equations of the Wilson-Polchinski renormalization group that describe the evolution of the finite-scale bias parameters with $\Lambda$, analogous to the $\beta$-function running in QFT. I will then discuss how the RG-flow of EFTofLSS can lead to improvements in the extraction of cosmological parameters and also serve as a tool for sanity checks.