Matter Creation by Cosmic Perturbations at 1-loop

by Azadeh Maleknejad (King's College London)

Wednesday 23 Apr 2025, 15:00 → 16:00 Europe/Berlin

build. 2a, SR2 (DESY Hamburg)

Fermions cannot be gravitationally produced at tree level in an expanding universe — unless they are extremely massive. However, this picture changes at the gravitational 1-loop level in the presence of cosmic perturbations, leading to a new and unavoidable mechanism for gravitational particle production. In this talk, I will explore the theory and phenomenological implications of this new effect, along with recent developments in this emerging direction.