Quantum Gravity Seminar: Mariana Carrillo González

Speaker: Mariana Carrillo González (Imperial Coll. London)

Spacetime coordinates: Wed @ 13:30, Auditorium A

Zoom Link: https://ucph-ku.zoom.us/j/9295289933?omn=67282578176

Title: Bounding cosmological EFTs

Abstract: It is known Wilson coefficients of an Effective Field Theory cannot take any value and still lead to physical descriptions without violations of causality and unitarity. In this talk, I will show the consequences of causality an unitarity on cosmological backgrounds focusing on two-point functions. On the first part, I will consider the consequences of causality on the EFT of inflation, particularly in a model that was proposed to give a large abundance of primordial black holes. Afterwards, I'll show how a positive spectral density in the Kahlen Lehman decomposition can impose bounds on the Wilson coefficients of the 2-point contributions of a spin 0 and spin 1 EFT in de Sitter.