# One-loop infrared rescattering by enhanced scalar fluctuations during inflation

- Institution: CERN
- Department: TH institutes
- Speaker: Sébastien Renaux-Petel
- Year: 2024
- Language: English
- Source: [CERN](https://videos.cern.ch/record/3020010)
- Licence: [CERN](http://copyright.web.cern.ch)
- Who can watch: Teens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

I will describe that, whenever the perturbations of some field are excited during inflation by a physical process on sub-horizon scales, they unavoidably generate, even through gravitational interactions alone, a significant resonant infrared cascade of power down to scales that are of the order of the horizon at that time. I will give general analytic one-loop results for the enhancement of the infrared power of the curvature perturbation generated by this effect, highlighting the role played by the resonance. I will also show lattice simulations result for this phenomenon, which can impact the phenomenology associated with a variety of mechanisms considered in the literature, notably concerning primordial black holes and gravitational waves..

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## Lectures

1. [One-loop infrared rescattering by enhanced scalar fluctuations during inflation](https://invisiblenetwork.ai/learn/cern/3020010/56f3018ae14b), 24 min (CERN's player)