Bounding Effective Field Theories: From Flat Space to Cosmological Spacetimes

by Dr Mariana Carrillo Gonzalez (Imperial College, London)

Thursday 29 Aug 2024, 14:00 → 15:00 Europe/Stockholm

AlbaNova A5:1041 - CoPS grupprum (AlbaNova Main Building)

N.B. New time.

 

Abstract: Effective Field Theories (EFTs) allow us to describe low-energy physics without knowing the specific UV completion. This comes at the cost of having free parameters (Wilson coefficients) whose values encode the UV physics but are not constrained from a standard EFT point of view. It is well known that some values can lead to unphysical properties of these theories. In this talk, I will present a low-energy technique to put bounds on these coefficients by requiring causal propagation. I will show how these bounds can be obtained in flat space and then move on to how to apply these techniques in cosmological spacetimes. Throughout the talk, I will present bounds on scalar and photon EFTs and show their complementarity to analytic positivity bounds.