Marc Schiffer: d=4 as the critical dimensionality of asymptotically safe interactions

In my talk, I explore the question why our universe is four dimensional from an asymptotically safe vantage point. I present indications that asymptotically safe quantum fluctuations of gravity could only solve the U(1) Landau-pole problem in the Standard Model in four dimensions. This could single out the observed dimensionality of the universe, once the requirement of a minimalistic description of the microscopic building blocks of our universe in terms of Standard Model fields together with a quantum-field theoretic description of quantum gravity is made. (Based on arXiv:1902.06479)