22–26 Jun 2020
CERN
Europe/Zurich timezone

Thermal friction in early cosmology

23 Jun 2020, 16:00
1h
Virtual only (CERN)

Virtual only

CERN

Speaker

Kim Berghaus (Johns Hopkins University)

Description

Zoom meeting: https://cern.zoom.us/j/7930190483 (password: see email)

Format: 40 minutes talk + 20 min discussion

Virtual Axion Institute: The discussion on this talk can be continued in Kim's virtual guest office.
https://mattermost.web.cern.ch/axions/channels/kim-berghaus

Abstract: Rolling scalar fields play an important role in understanding cosmology within a particle physics framework. Coupling a rolling scalar field to light degrees of freedom gives rise to a thermal friction which, if large enough, induces a thermal bath. In the context of inflation the presence of such a thermal bath has compelling consequences as it significantly alters the usual observables, leading to a suppression of the tensor-to-scalar ratio r and a unique prediction for non-gaussianities. In my talk, I will illuminate why the axion of a non-Abelian gauge group is the ideal candidate for generating the thermal friction and how it sets the stage for a minimal setup of warm inflation, as well as a potential solution to the Hubble tension.

Presentation materials