Speaker
Description
It turns out that imposing reflecting boundary conditions at the Big Bang singularity itself is sufficient to explain the CMB Power spectrum without the assumption of an exotic epoch preceding radiation era. However, there are well known problems with starting the Universe in a radiation dominated phase such as the horizon problem, overproduction of dark matter, and thermalization of gravitons. In this talk I will explain how quadratic curvature terms in the gravitational action can avoid these issues while imposing constraints on the Weyl squared coupling. We will also discuss how the Big Bang singularity can be avoided in a theory with Weyl symmetry and discuss a toy model QFT that looks close to the Standard Model which is anomaly free and has a well-defined UV completion on a curved background. We use the exact renormalization group to study this Weyl anomaly.
| Affiliation | Higgs Centre for Theoretical Physics, University of Edinburgh |
|---|---|
| Career status | PhD student |