Quantum Gravity Seminar: Neil Turok

Speaker:Neil Turok (University of Edinburgh and Perimeter Institute for Theoretical Physics)

Spacetime coordinates: Wed @ 14:30, Auditorium A

Zoom Link: https://ucph-ku.zoom.us/j/9295289933?omn=67282578176

Title: A simple unified theory

Abstract:Observations of the universe on very large and very small scales are well-fit by known physics with only minimal extensions. In contrast, many unified theories hold that the universe is extremely complex on the tiniest scales and wildly chaotic on large ones. In this talk, I will outline a simpler, more predictive approach to unification, guided strongly by the observations and insisting on a minimum of theoretical assumptions and parameters. The underlying hypothesis is that the Universe respects CPT symmetry. This leads to a resolution of the big bang singularity and a thermodynamic explanation for the large-scale geometry of the cosmos, including a small positive cosmological constant. There is no need for inflation. The dark matter consists of right-handed neutrinos, a modest extension of the Standard Model (SM) required for other reasons. The theory predicts three generations of SM fermions and quantitatively explains the large-scale cosmic density variations in terms of SM parameters. It yields a new picture of the Higgs mechanism with the potential to resolve the gauge-gravity hierarchy puzzle. If these successes are an indication, we may be on a new path to understanding nature’s most basic physical laws.