Speaker
Description
This talk gives a broad introduction into an emerging field at the interface of quantum foundations and quantum gravity. What connects these different research areas are common questions of shared interest: What is the causal structure at the quantum level? What is the role of the equivalence principle at the quantum level? Are the reference frames classical or quantum? After a brief introduction, I will explain the practical relevance of these questions for the characteristic null initial problem, in which we seek a quantization of gravity from observables on a light-cone. In four spacetime dimensions, several simplifications occur. For a specific class of impulsive gravitational null initial data (shock-waves), it is possible to find a complete and non-perturbative quantization on the light cone. One of the quantum numbers is the total luminosity carried to infinity. A transition happens when the luminosity reaches the Planck power. Below the Planck power, the spectrum of the radiated power is discrete. Above the Planck power, the spectrum is continuous. The talk is based on arXiv:2402.12578, arXiv:2401.17491, arXiv:2302.12799.
