Quantum Gravity Seminar: Neil Turok

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

Spacetime coordinates: Wed @ 14:30, Auditorium A

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

Title: A minimal SM/LCDM cosmology

Abstract: Observations of the universe continue to be well-fit by the SM on small scales and LCDM on large scales. What should we make of this surprising simplicity? Perhaps the universe really is simple and predictable: if so, we may be close to understanding physics’ most basic laws. Boyle and I recently proposed that the universe respects CPT symmetry. This simple but radical idea turns out to explain LCDM’s main features and to make several new predictions. The big bang singularity is resolved by conformal symmetry. The dark matter consists of stable, RH neutrinos. The large-scale geometry is explained thermodynamically without inflation. The zero-point vacuum energy divergence and the trace anomalies of the SM are cancelled by a new mechanism predicting 3 generations of SM fermions and potentially explaining the gauge-gravity hierarchy. With minimal assumptions, it also predicts scale-invariant, adiabatic, density fluctuations with an amplitude and red tilt governed by SM parameters. in remarkable agreement with observation.  If time allows I’ll explain how CPT symmetry leads to a new resolution of the theoretical puzzles associated with black holes.