Geodesic deviation in field space: flattened non-gaussianities and PBH
Aula 507 (Pere Pascual, ICC building, UAB Campus)
27/02/2020 - 00/00/0000
Several recent proposals to embed in?ation into high-energy physics rely on in?ationary dynamics characterized by a strongly non-geodesic motion. This in turn relaxes the conditions of slow-roll to allow for potentials that are steep in Planck units, a welcome feature in view of the eta problem and the recently much discussed swampland conjectures.

In this talk I will present a general framework to study non-Gaussianities in the presence of non-geodesic trajectories in field space. I will then highlight how non-geodesic motion in field space naturally leads to “hyper-non-Gaussianities”, i.e. the bispectrum and all higher-order correlation functions are hierarchically enhanced for particular flattened configurations.

Towards the end I will discuss how a similar mechanism can induce a significant enhancement of the power spectrum on small scales providing an interesting new possibility to generate primordial black holes.
Attached Documents
Generalitat de CatalunyaUniversitat de BarcelonaUniversitat Autònoma de BarcelonaUniversitat Politècnica de CatalunyaConsejo Superior de Investigaciones CientíficasCentres de Recerca de Catalunya